Merge branch 'master' into release/6.0

updated changelog
bump version to 6.0
2017-09-27 00:35:49 +02:00 · 2017-09-27 00:34:57 +02:00 · 2017-09-26 23:51:08 +02:00 · 2017-09-26 23:50:56 +02:00 · 2017-09-26 23:45:25 +02:00 · 2017-09-21 22:26:19 +02:00
86 changed files with 5391 additions and 3295 deletions
@@ -0,0 +1 @@
+4
@@ -1,19 +1,49 @@
-language: objective-c
-osx_image: xcode7.2
+matrix:
+  allow_failures:
+    - os: linux
+  include:
+    - script:
+        - set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme Dip -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 6,OS=10.1' ONLY_ACTIVE_ARCH=NO | xcpretty -c
+        - set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme Dip -sdk macosx -destination 'platform=macOS,arch=x86_64' ONLY_ACTIVE_ARCH=NO | xcpretty -c
+        - set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme Dip -sdk appletvsimulator -destination 'platform=tvOS Simulator,name=Apple TV 1080p,OS=latest' ONLY_ACTIVE_ARCH=NO | xcpretty -c
+        # disable running watchos until https://github.com/travis-ci/travis-ci/issues/7580 is fixed
+        #- set -o pipefail && xcodebuild -workspace Dip.xcworkspace -scheme Dip -sdk watchsimulator -destination 'platform=watchOS Simulator,name=Apple Watch - 38mm,OS=latest' ONLY_ACTIVE_ARCH=NO | xcpretty - c
+        - set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme DipSampleApp -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 6,OS=10.1' ONLY_ACTIVE_ARCH=NO | xcpretty -c
+        - pod spec lint --allow-warnings
+        - carthage build --no-skip-current
+      os: osx
+      osx_image: xcode9
+      language: objective-c
+      before_install:
+        - gem install cocoapods --version 1.1.0.rc.2 --no-document
+    - script:
+        - swift package clean && swift build && swift test
+      os: linux
+      dist: trusty
+      sudo: required
+      language: generic
+      before_install:
+        - wget -q -O - https://swift.org/keys/all-keys.asc | gpg --import -
+        - cd ..
+        - export SWIFT_VERSION=swift-4.0-RELEASE
+        - wget https://swift.org/builds/swift-4.0-release/ubuntu1404/$SWIFT_VERSION/$SWIFT_VERSION-ubuntu14.04.tar.gz
+        - tar xzf $SWIFT_VERSION-ubuntu14.04.tar.gz
+        - export PATH="${PWD}/${SWIFT_VERSION}-ubuntu14.04/usr/bin:${PATH}"
+        - cd Dip
+    - script:
+        - swift package clean && swift build && swift test
+      os: linux
+      dist: trusty
+      sudo: required
+      language: generic
+      before_install:
+        - wget -q -O - https://swift.org/keys/all-keys.asc | gpg --import -
+        - cd ..
+        - export SWIFT_VERSION=swift-3.1-RELEASE
+        - wget https://swift.org/builds/swift-3.1-release/ubuntu1404/$SWIFT_VERSION/$SWIFT_VERSION-ubuntu14.04.tar.gz
+        - tar xzf $SWIFT_VERSION-ubuntu14.04.tar.gz
+        - export PATH="${PWD}/${SWIFT_VERSION}-ubuntu14.04/usr/bin:${PATH}"
+        - cd Dip

-# cache: cocoapods
-# before_install:
-# - gem install cocoapods # Since Travis is not always on latest version
-
-install:
- gem install xcpretty --no-rdoc --no-ri --no-document --quiet
- curl -OlL "https://github.com/Carthage/Carthage/releases/download/0.11/Carthage.pkg" && sudo installer -pkg "Carthage.pkg" -target / && rm "Carthage.pkg"
-
-script:
- set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme Dip-iOS -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 6,OS=latest' ONLY_ACTIVE_ARCH=NO | xcpretty -c
- set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme Dip-OSX -sdk macosx -destination 'platform=OS X,arch=x86_64' ONLY_ACTIVE_ARCH=NO | xcpretty -c
- set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme Dip-tvOS -sdk appletvsimulator -destination 'platform=tvOS Simulator,name=Apple TV 1080p,OS=latest' ONLY_ACTIVE_ARCH=NO | xcpretty -c
- set -o pipefail && xcodebuild -workspace Dip.xcworkspace -scheme Dip-watchOS -sdk watchsimulator -destination 'platform=watchOS Simulator,name=Apple Watch - 38mm,OS=latest' ONLY_ACTIVE_ARCH=NO | xcpretty - c
- set -o pipefail && xcodebuild test -workspace Dip.xcworkspace -scheme DipSampleApp -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 6,OS=latest' ONLY_ACTIVE_ARCH=NO | xcpretty -c
- pod lib lint --quick
- carthage build --no-skip-current
+notifications:
+  email: false
@@ -1,5 +1,136 @@
 # CHANGELOG

+## 6.0
+
+* Swift 4 support
+* Fixed unneeded reuse of singletons in collaborating containers. 
+  Containers now first attempt to autowire components and fallback to collaboration when it fails.  
+  [#169](https://github.com/AliSoftware/Dip/issues/169), [@ilyapuchka](https://github.com/ilyapuchka)
+
+## 5.1
+
+* Dropped Swift 2.3 support.  
+  [#150](https://github.com/AliSoftware/Dip/issues/150), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added custom logging function.  
+  [#146](https://github.com/AliSoftware/Dip/issues/146), [@Pr0Ger](https://github.com/Pr0Ger)
+  
+#### Fixed
+
+* Fixed Swift 3.1 warnings.  
+  [#145](https://github.com/AliSoftware/Dip/issues/145), [@DenHeadless](https://github.com/DenHeadless)
+* Fixed collaboration shared references.  
+  [#151](https://github.com/AliSoftware/Dip/issues/151), [@ilyapuchka](https://github.com/ilyapuchka)
+* Fixed autowiring when using tags.  
+  [#154](https://github.com/AliSoftware/Dip/issues/154), [@ilyapuchka](https://github.com/ilyapuchka)
+
+## 5.0.4
+
+#### Fixed
+
+* Fixed broken compatibility for Swift 2.3 API in `resolve(tag:arguments:)` method.  
+  [#135](https://github.com/AliSoftware/Dip/issues/135), [@ilyapuchka](https://github.com/ilyapuchka)
+  
+## 5.0.3
+
+* Added Swift 2.3 compatibility. `swift2.3` brunch is no longer maintained.  
+  [#127](https://github.com/AliSoftware/Dip/issues/127), [@ilyapuchka](https://github.com/ilyapuchka)
+
+#### Fixed
+
+* Fixed reusing instances registered with `WeakSingleton` scope  
+  [#129](https://github.com/AliSoftware/Dip/issues/129), [@ilyapuchka](https://github.com/ilyapuchka)
+
+## 5.0.2
+
+#### Fixed
+
+* Fixed Swift 3 issues related to reflection and IUO  
+  [#125](https://github.com/AliSoftware/Dip/issues/125), [@ilyapuchka](https://github.com/ilyapuchka)
+
+## 5.0.1
+
+This release is the same as 5.0.0 and only fixes CocoaPods speck pushed to trunk without macOS, tvOS and watchOS deployment targets. Please use this release instead of 5.0.0 if you integrate Dip via Cocoapods.
+
+## 5.0.0
+
+* Migrated to Swift 3.0  
+  [#120](https://github.com/AliSoftware/Dip/issues/120), [@patrick-lind](https://github.com/patrick-lind), [@mark-urbanthings](https://github.com/mark-urbanthings), [@ilyapuchka](https://github.com/ilyapuchka)
+* Renamed `DefinitionOf` to `Definition` and some other source-breaking refactoring.  
+  [#113](https://github.com/AliSoftware/Dip/issues/113), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added `invalidType` error when resolved instance does not implement requested type.  
+  [#118](https://github.com/AliSoftware/Dip/issues/118), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added optional `type` parameter in register methods to be able to specify type when registering using method literal instead of closure.
+  [#115](https://github.com/AliSoftware/Dip/issues/115), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added `implements` family of methods in to `Definition` to register type-forwarding definitions.  
+  [#114](https://github.com/AliSoftware/Dip/issues/114), [@ilyapuchka](https://github.com/ilyapuchka)
+* Shared scope is now the default scope.  
+  [#112](https://github.com/AliSoftware/Dip/issues/112), [@ilyapuchka](https://github.com/ilyapuchka)
+* Single target project setup.  
+  [#121](https://github.com/AliSoftware/Dip/issues/121), [@ilyapuchka](https://github.com/ilyapuchka)
+* Simplified implementation of auto-wiring.  
+  [#117](https://github.com/AliSoftware/Dip/issues/117), [@ilyapuchka](https://github.com/ilyapuchka)
+
+
+#### Fixed
+* Auto-injected properties inherited from super class are now properly injected when resolving subclass. 
+Added `resolveDependencies(_:DependencyContainer)` method to `Resolvable` protocol to handle inheritance when resolving.  
+  [#116](https://github.com/AliSoftware/Dip/issues/116), [@ilyapuchka](https://github.com/ilyapuchka)
+  
+  
+## 4.6.1
+
+#### Fixed
+
+* Fixed sharing singletons between collaborating containers.  
+  [#103](https://github.com/AliSoftware/Dip/issues/103), [@ilyapuchka](https://github.com/ilyapuchka)
+* Renamed some public API's (see release notes for more info).  
+  [#105](https://github.com/AliSoftware/Dip/issues/105), [@ilyapuchka](https://github.com/ilyapuchka)
+
+## 4.6.0
+
+* Containers collaboration. Break your definitions in modules and link them together.  
+  [#95](https://github.com/AliSoftware/Dip/pull/95), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added WeakSingleton scope.  
+  [#96](https://github.com/AliSoftware/Dip/pull/96), [@ilyapuchka](https://github.com/ilyapuchka)
+* Properties Auto-injection now is performed before calling `resolveDependencies` block  
+  [#97](https://github.com/AliSoftware/Dip/pull/97), [@ilyapuchka](https://github.com/ilyapuchka)
+* Fixed updating container's context when resolving properties with auto-injection.  
+  [#98](https://github.com/AliSoftware/Dip/pull/98), [@ilyapuchka](https://github.com/ilyapuchka) 
+* Improved logging.  
+  [#94](https://github.com/AliSoftware/Dip/pull/94), [#99](https://github.com/AliSoftware/Dip/pull/99), [@ilyapuchka](https://github.com/ilyapuchka)
+* Fixed warning about using only extensions api.  
+  [#92](https://github.com/AliSoftware/Dip/pull/92), [@mwoollard](https://github.com/mwoollard)
+
+## 4.5.0
+
+* Added weakly-typed API to resolve components when exact type is unknown during compile time.  
+  [#79](https://github.com/AliSoftware/Dip/pull/79), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added type forwarding feature. You can register the same factory to resolve different types.  
+  [#89](https://github.com/AliSoftware/Dip/pull/89), [@ilyapuchka](https://github.com/ilyapuchka) 
+* Container now can resolve optional types :tada:  
+  [#84](https://github.com/AliSoftware/Dip/pull/84), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added container context that provides contextual information during graph resolution process.  
+  [#83](https://github.com/AliSoftware/Dip/pull/83), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added method to validate container configuration.  
+  [#87](https://github.com/AliSoftware/Dip/pull/87), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added method to manually set value wrapped by auto-injection wrappers.  
+  [#81](https://github.com/AliSoftware/Dip/pull/81), [@ilyapuchka](https://github.com/ilyapuchka)
+* Added separate error type for failures during auto-wiring.  
+  [#85](https://github.com/AliSoftware/Dip/pull/85), [@ilyapuchka](https://github.com/ilyapuchka)
+
+
+## 4.4.0
+
+* Added `.EagerSingleton` scope for objectes requiring early instantiation and `bootstrap()` method on `DepenencyContainer`.  
+  [#65](https://github.com/AliSoftware/Dip/pull/65), [@ilyapuchka](https://github.com/ilyapuchka)
+* Reverted order of `Resolvable` callbacks.  
+  [#67](https://github.com/AliSoftware/Dip/pull/67), [@ilyapuchka](https://github.com/ilyapuchka)
+
+## 4.3.1
+
+* Fix Swift 2.2 compile errors in tests.  
+  [#62](https://github.com/AliSoftware/Dip/pull/62), [@mwoollard](https://github.com/mwoollard)
+
 ## 4.3.0

 * Added `DependencyTagConvertible` protocol for better typed tags.  
@@ -101,7 +232,7 @@
  This code: 
  
  ```swift
-  container.register("some tag") { SomeClass() as SomeProtocol }
+  container.register(tag: "some tag") { SomeClass() as SomeProtocol }
  container.resolve("some tag") as SomeProtocol
  ```
  
@@ -1,21 +1,13 @@
 Pod::Spec.new do |s|
  s.name             = "Dip"
-  s.version          = "4.3.0"
-  s.summary          = "A simple Dependency Resolver: Dependency Injection using Protocol resolution."
+  s.version          = "6.0"
+  s.summary          = "Dependency Injection for Swift made easy."

  s.description      = <<-DESC
-                        Dip is a Swift framework to manage your Dependencies between your classes
-                        in your app using Dependency Injection.
-
-                        It's aimed to be very simple to use while improving testability
-                        of your app by allowing you to get rid of those sharedInstances and instead
-                        inject values based on protocol resolution.
-
-                        Define your API using a protocol, then ask Dip to resolve this protocol into
-                        an instance dynamically in your classes. Then your App and your Tests can be
-                        configured to resolve the protocol using a different instance or class so this
-                        improve testability by decoupling the API and the concrete class used to implement it.
-                       DESC
+                        Dip is a Swift Dependency Injection Container.
+                        It provides reusable functionality for managing dependencies of your types 
+                        and will help you to wire up different parts of your app.
+                        DESC

  s.homepage         = "https://github.com/AliSoftware/Dip"
  s.license          = 'MIT'
@@ -1,100 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Scheme
-   LastUpgradeVersion = "0710"
-   version = "1.3">
-   <BuildAction
-      parallelizeBuildables = "YES"
-      buildImplicitDependencies = "YES">
-      <BuildActionEntries>
-         <BuildActionEntry
-            buildForTesting = "YES"
-            buildForRunning = "YES"
-            buildForProfiling = "YES"
-            buildForArchiving = "YES"
-            buildForAnalyzing = "YES">
-            <BuildableReference
-               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "0903B3771C1615EC002241C1"
-               BuildableName = "Dip.framework"
-               BlueprintName = "Dip-iOS"
-               ReferencedContainer = "container:Dip.xcodeproj">
-            </BuildableReference>
-         </BuildActionEntry>
-      </BuildActionEntries>
-   </BuildAction>
-   <TestAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES"
-      codeCoverageEnabled = "YES">
-      <Testables>
-         <TestableReference
-            skipped = "NO">
-            <BuildableReference
-               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "0903B3801C1615EC002241C1"
-               BuildableName = "Dip-iOSTests.xctest"
-               BlueprintName = "Dip-iOSTests"
-               ReferencedContainer = "container:Dip.xcodeproj">
-            </BuildableReference>
-         </TestableReference>
-      </Testables>
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B3771C1615EC002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-iOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-      <AdditionalOptions>
-      </AdditionalOptions>
-   </TestAction>
-   <LaunchAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      launchStyle = "0"
-      useCustomWorkingDirectory = "NO"
-      ignoresPersistentStateOnLaunch = "NO"
-      debugDocumentVersioning = "YES"
-      debugServiceExtension = "internal"
-      allowLocationSimulation = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B3771C1615EC002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-iOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-      <AdditionalOptions>
-      </AdditionalOptions>
-   </LaunchAction>
-   <ProfileAction
-      buildConfiguration = "Release"
-      shouldUseLaunchSchemeArgsEnv = "YES"
-      savedToolIdentifier = ""
-      useCustomWorkingDirectory = "NO"
-      debugDocumentVersioning = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B3771C1615EC002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-iOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-   </ProfileAction>
-   <AnalyzeAction
-      buildConfiguration = "Debug">
-   </AnalyzeAction>
-   <ArchiveAction
-      buildConfiguration = "Release"
-      revealArchiveInOrganizer = "YES">
-   </ArchiveAction>
-</Scheme>
@@ -1,99 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Scheme
-   LastUpgradeVersion = "0710"
-   version = "1.3">
-   <BuildAction
-      parallelizeBuildables = "YES"
-      buildImplicitDependencies = "YES">
-      <BuildActionEntries>
-         <BuildActionEntry
-            buildForTesting = "YES"
-            buildForRunning = "YES"
-            buildForProfiling = "YES"
-            buildForArchiving = "YES"
-            buildForAnalyzing = "YES">
-            <BuildableReference
-               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "0903B3A51C1618AF002241C1"
-               BuildableName = "Dip.framework"
-               BlueprintName = "Dip-tvOS"
-               ReferencedContainer = "container:Dip.xcodeproj">
-            </BuildableReference>
-         </BuildActionEntry>
-      </BuildActionEntries>
-   </BuildAction>
-   <TestAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES">
-      <Testables>
-         <TestableReference
-            skipped = "NO">
-            <BuildableReference
-               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "0903B3AE1C1618AF002241C1"
-               BuildableName = "Dip-tvOSTests.xctest"
-               BlueprintName = "Dip-tvOSTests"
-               ReferencedContainer = "container:Dip.xcodeproj">
-            </BuildableReference>
-         </TestableReference>
-      </Testables>
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B3A51C1618AF002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-tvOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-      <AdditionalOptions>
-      </AdditionalOptions>
-   </TestAction>
-   <LaunchAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      launchStyle = "0"
-      useCustomWorkingDirectory = "NO"
-      ignoresPersistentStateOnLaunch = "NO"
-      debugDocumentVersioning = "YES"
-      debugServiceExtension = "internal"
-      allowLocationSimulation = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B3A51C1618AF002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-tvOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-      <AdditionalOptions>
-      </AdditionalOptions>
-   </LaunchAction>
-   <ProfileAction
-      buildConfiguration = "Release"
-      shouldUseLaunchSchemeArgsEnv = "YES"
-      savedToolIdentifier = ""
-      useCustomWorkingDirectory = "NO"
-      debugDocumentVersioning = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B3A51C1618AF002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-tvOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-   </ProfileAction>
-   <AnalyzeAction
-      buildConfiguration = "Debug">
-   </AnalyzeAction>
-   <ArchiveAction
-      buildConfiguration = "Release"
-      revealArchiveInOrganizer = "YES">
-   </ArchiveAction>
-</Scheme>
@@ -1,80 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Scheme
-   LastUpgradeVersion = "0710"
-   version = "1.3">
-   <BuildAction
-      parallelizeBuildables = "YES"
-      buildImplicitDependencies = "YES">
-      <BuildActionEntries>
-         <BuildActionEntry
-            buildForTesting = "YES"
-            buildForRunning = "YES"
-            buildForProfiling = "YES"
-            buildForArchiving = "YES"
-            buildForAnalyzing = "YES">
-            <BuildableReference
-               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "0903B4031C162862002241C1"
-               BuildableName = "Dip.framework"
-               BlueprintName = "Dip-watchOS"
-               ReferencedContainer = "container:Dip.xcodeproj">
-            </BuildableReference>
-         </BuildActionEntry>
-      </BuildActionEntries>
-   </BuildAction>
-   <TestAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES">
-      <Testables>
-      </Testables>
-      <AdditionalOptions>
-      </AdditionalOptions>
-   </TestAction>
-   <LaunchAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      launchStyle = "0"
-      useCustomWorkingDirectory = "NO"
-      ignoresPersistentStateOnLaunch = "NO"
-      debugDocumentVersioning = "YES"
-      debugServiceExtension = "internal"
-      allowLocationSimulation = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B4031C162862002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-watchOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-      <AdditionalOptions>
-      </AdditionalOptions>
-   </LaunchAction>
-   <ProfileAction
-      buildConfiguration = "Release"
-      shouldUseLaunchSchemeArgsEnv = "YES"
-      savedToolIdentifier = ""
-      useCustomWorkingDirectory = "NO"
-      debugDocumentVersioning = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "0903B4031C162862002241C1"
-            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-watchOS"
-            ReferencedContainer = "container:Dip.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-   </ProfileAction>
-   <AnalyzeAction
-      buildConfiguration = "Debug">
-   </AnalyzeAction>
-   <ArchiveAction
-      buildConfiguration = "Release"
-      revealArchiveInOrganizer = "YES">
-   </ArchiveAction>
-</Scheme>
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0710"
+   LastUpgradeVersion = "0900"
   version = "1.3">
   <BuildAction
      parallelizeBuildables = "YES"
@@ -16,7 +16,21 @@
               BuildableIdentifier = "primary"
               BlueprintIdentifier = "0903B3571C161543002241C1"
               BuildableName = "Dip.framework"
-               BlueprintName = "Dip-OSX"
+               BlueprintName = "Dip"
+               ReferencedContainer = "container:Dip.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "NO"
+            buildForProfiling = "NO"
+            buildForArchiving = "NO"
+            buildForAnalyzing = "NO">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "0903B3601C161543002241C1"
+               BuildableName = "DipTests.xctest"
+               BlueprintName = "DipTests"
               ReferencedContainer = "container:Dip.xcodeproj">
            </BuildableReference>
         </BuildActionEntry>
@@ -26,15 +40,17 @@
      buildConfiguration = "Debug"
      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES">
+      language = ""
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      codeCoverageEnabled = "YES">
      <Testables>
         <TestableReference
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
               BlueprintIdentifier = "0903B3601C161543002241C1"
-               BuildableName = "Dip-OSXTests.xctest"
-               BlueprintName = "Dip-OSXTests"
+               BuildableName = "DipTests.xctest"
+               BlueprintName = "DipTests"
               ReferencedContainer = "container:Dip.xcodeproj">
            </BuildableReference>
         </TestableReference>
@@ -44,7 +60,7 @@
            BuildableIdentifier = "primary"
            BlueprintIdentifier = "0903B3571C161543002241C1"
            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-OSX"
+            BlueprintName = "Dip"
            ReferencedContainer = "container:Dip.xcodeproj">
         </BuildableReference>
      </MacroExpansion>
@@ -55,6 +71,7 @@
      buildConfiguration = "Debug"
      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
      launchStyle = "0"
      useCustomWorkingDirectory = "NO"
      ignoresPersistentStateOnLaunch = "NO"
@@ -66,7 +83,7 @@
            BuildableIdentifier = "primary"
            BlueprintIdentifier = "0903B3571C161543002241C1"
            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-OSX"
+            BlueprintName = "Dip"
            ReferencedContainer = "container:Dip.xcodeproj">
         </BuildableReference>
      </MacroExpansion>
@@ -84,7 +101,7 @@
            BuildableIdentifier = "primary"
            BlueprintIdentifier = "0903B3571C161543002241C1"
            BuildableName = "Dip.framework"
-            BlueprintName = "Dip-OSX"
+            BlueprintName = "Dip"
            ReferencedContainer = "container:Dip.xcodeproj">
         </BuildableReference>
      </MacroExpansion>
@@ -1,9 +0,0 @@
-import PackageDescription
-
-let package = Package(
-        name: "DipTests",
-        dependencies: [
-                .Package(url: "../../../Dip", majorVersion: 4, minor: 2),
-        ]
-)
-
@@ -1,299 +0,0 @@
-//
-// Dip
-//
-// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-//
-
-import XCTest
-@testable import Dip
-
-private protocol Service: class { }
-private class ServiceImp1: Service { }
-private class ServiceImp2: Service { }
-
-private protocol AutoWiredClient: class {
-  var service1: Service! { get set }
-  var service2: Service! { get set }
-}
-
-private class AutoWiredClientImp: AutoWiredClient {
-  var service1: Service!
-  var service2: Service!
-  
-  init(service1: Service, service2: ServiceImp2) {
-    self.service1 = service1
-    self.service2 = service2
-  }
-  init() {}
-}
-
-class AutoWiringTests: XCTestCase {
-  
-  let container = DependencyContainer()
-
-  #if os(Linux)
-  var allTests: [(String, () throws -> Void)] {
-    return [
-      ("testThatItCanResolveWithAutoWiring", testThatItCanResolveWithAutoWiring),
-      ("testThatItUsesAutoWireFactoryWithMostNumberOfArguments", testThatItUsesAutoWireFactoryWithMostNumberOfArguments),
-      ("testThatItThrowsAmbiguityErrorWhenUsingAutoWire", testThatItThrowsAmbiguityErrorWhenUsingAutoWire),
-      ("testThatItFirstTriesToUseTaggedFactoriesWhenUsingAutoWire", testThatItFirstTriesToUseTaggedFactoriesWhenUsingAutoWire),
-      ("testThatItFallbackToNotTaggedFactoryWhenUsingAutoWire", testThatItFallbackToNotTaggedFactoryWhenUsingAutoWire),
-      ("testThatItDoesNotTryToUseAutoWiringWhenCallingResolveWithArguments", testThatItDoesNotTryToUseAutoWiringWhenCallingResolveWithArguments),
-      ("testThatItDoesNotUseAutoWiringWhenFailedToResolveLowLevelDependency", testThatItDoesNotUseAutoWiringWhenFailedToResolveLowLevelDependency),
-      ("testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgain", testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgain),
-      ("testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithTheSameTagged", testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithTheSameTagged),
-      ("testThatItDoesNotReuseInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithNoTag", testThatItDoesNotReuseInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithNoTag)
-    ]
-  }
-
-  func setUp() {
-    container.reset()
-  }
-  #else
-  override func setUp() {
-    container.reset()
-  }
-  #endif
-
-  func testThatItCanResolveWithAutoWiring() {
-    //given
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-    
-    //when
-    let client = try! container.resolve() as AutoWiredClient
-    
-    //then
-    let service1 = client.service1
-    XCTAssertTrue(service1 is ServiceImp1)
-    let service2 = client.service2
-    XCTAssertTrue(service2 is ServiceImp2)
-  }
-  
-  func testThatItUsesAutoWireFactoryWithMostNumberOfArguments() {
-    //given
-    
-    //1 arg
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
-    //1 arg
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }
-    
-    //2 args
-    var factoryWithMostNumberOfArgumentsCalled = false
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-      .resolveDependencies { _ in
-        factoryWithMostNumberOfArgumentsCalled = true
-    }
-    
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    //when
-    let _ = try! container.resolve() as AutoWiredClient
-    
-    //then
-    XCTAssertTrue(factoryWithMostNumberOfArgumentsCalled)
-  }
-  
-  func testThatItThrowsAmbiguityErrorWhenUsingAutoWire() {
-    //given
-    
-    //1 arg
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
-    //1 arg
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }
-    
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    //when
-    AssertThrows(expression: try container.resolve() as AutoWiredClient) { error -> Bool in
-      switch error {
-      case DipError.AmbiguousDefinitions: return true
-      default: return false
-      }
-    }
-  }
-  
-  func testThatItFirstTriesToUseTaggedFactoriesWhenUsingAutoWire() {
-    //given
-    
-    //1 arg
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
-    //1 arg
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }
-    
-    //2 args
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-    
-    //1 arg tagged
-    var taggedFactoryWithMostNumberOfArgumentsCalled = false
-    container.register(tag: "tag", .ObjectGraph) { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
-    
-    //2 arg tagged
-    container.register(tag: "tag", .ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }.resolveDependencies { _ in
-      taggedFactoryWithMostNumberOfArgumentsCalled = true
-    }
-
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    //when
-    let _ = try! container.resolve(tag: "tag") as AutoWiredClient
-    
-    //then
-    XCTAssertTrue(taggedFactoryWithMostNumberOfArgumentsCalled)
-  }
-  
-  func testThatItFallbackToNotTaggedFactoryWhenUsingAutoWire() {
-    //given
-    
-    //1 arg
-    var notTaggedFactoryWithMostNumberOfArgumentsCalled = false
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }.resolveDependencies {_ in
-      notTaggedFactoryWithMostNumberOfArgumentsCalled = true
-    }
-    
-    //1 arg tagged
-    container.register(tag: "tag", .ObjectGraph) { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
-    
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    //when
-    let _ = try! container.resolve(tag: "other tag") as AutoWiredClient
-    
-    //then
-    XCTAssertTrue(notTaggedFactoryWithMostNumberOfArgumentsCalled)
-  }
-  
-  func testThatItDoesNotTryToUseAutoWiringWhenCallingResolveWithArguments() {
-    //given
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    //when
-    let service = try! container.resolve() as Service
-    AssertThrows(expression: try container.resolve(withArguments: service) as AutoWiredClient,
-      "Container should not use auto-wiring when resolving with runtime arguments")
-  }
-  
-  func testThatItDoesNotUseAutoWiringWhenFailedToResolveLowLevelDependency() {
-    //given
-    container.register(.ObjectGraph) { AutoWiredClientImp() as AutoWiredClient }
-      .resolveDependencies { container, resolved in
-        resolved.service1 = try container.resolve() as Service
-        resolved.service2 = try container.resolve() as ServiceImp2
-        
-        //simulate that something goes wrong on the way
-        throw DipError.DefinitionNotFound(key: DefinitionKey(protocolType: ServiceImp1.self, factoryType: Any.self))
-    }
-    
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-      .resolveDependencies { container, resolved in
-        //auto-wiring should be performed only when definition for type to resolve is not found
-        //but not for any other type along the way in the graph
-        XCTFail("Auto-wiring should not be performed if instance was actually resolved.")
-    }
-    
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    //then
-    AssertThrows(expression: try container.resolve() as AutoWiredClient,
-      "Container should not use auto-wiring when definition for resolved type is registered.")
-  }
-  
-  func testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgain() {
-    
-    //given
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    var anotherInstance: AutoWiredClient?
-    
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-      .resolveDependencies { container, _ in
-        if anotherInstance == nil {
-          anotherInstance = try! container.resolve() as AutoWiredClient
-        }
-    }
-    
-    //when
-    let resolved = try! container.resolve() as AutoWiredClient
-    
-    //then
-    //when doing another auto-wiring during resolve we should reuse instance
-    XCTAssertTrue((resolved as! AutoWiredClientImp) === (anotherInstance as! AutoWiredClientImp))
-  }
-  
-  func testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithTheSameTagged() {
-    
-    //given
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    var anotherInstance: AutoWiredClient?
-    
-    container.register(tag: "tag", .ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-      .resolveDependencies { container, _ in
-        if anotherInstance == nil {
-          anotherInstance = try! container.resolve(tag: "tag") as AutoWiredClient
-        }
-    }
-    
-    //when
-    let resolved = try! container.resolve(tag: "tag") as AutoWiredClient
-    
-    //then
-    //when doing another auto-wiring during resolve we should reuse instance
-    XCTAssertTrue((resolved as! AutoWiredClientImp) === (anotherInstance as! AutoWiredClientImp))
-  }
-  
-  func testThatItDoesNotReuseInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithNoTag() {
-    
-    //given
-    container.register(.ObjectGraph) { ServiceImp1() as Service }
-    container.register(.ObjectGraph) { ServiceImp2() }
-    
-    var anotherInstance: AutoWiredClient?
-    
-    container.register(.ObjectGraph) { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
-      .resolveDependencies { container, _ in
-        if anotherInstance == nil {
-          anotherInstance = try! container.resolve() as AutoWiredClient
-        }
-    }
-    
-    //when
-    let resolved = try! container.resolve(tag: "tag") as AutoWiredClient
-    
-    //then
-    //when doing another auto-wiring during resolve we should reuse instance
-    XCTAssertTrue((resolved as! AutoWiredClientImp) !== (anotherInstance as! AutoWiredClientImp))
-  }
-  
-}
-
@@ -1,222 +0,0 @@
-//
-// Dip
-//
-// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-//
-
-import XCTest
-@testable import Dip
-
-private protocol Service: class {}
-private class ServiceImp1: Service {}
-private class ServiceImp2: Service {}
-
-private class Server {
-  weak var client: Client?
-  
-  init() {}
-}
-
-private class Client {
-  var server: Server
-  
-  init(server: Server) {
-    self.server = server
-  }
-}
-
-class ComponentScopeTests: XCTestCase {
-  
-  let container = DependencyContainer()
-  
-  #if os(Linux)
-  var allTests: [(String, () throws -> Void)] {
-    return [
-      ("testThatPrototypeIsDefaultScope", testThatPrototypeIsDefaultScope),
-      ("testThatScopeCanBeChanged", testThatScopeCanBeChanged),
-      ("testThatItResolvesTypeAsNewInstanceForPrototypeScope", testThatItResolvesTypeAsNewInstanceForPrototypeScope),
-      ("testThatItReusesInstanceForSingletonScope", testThatItReusesInstanceForSingletonScope),
-      ("testThatSingletonIsNotReusedAcrossContainers", testThatSingletonIsNotReusedAcrossContainers),
-      ("testThatSingletonIsReleasedWhenDefinitionIsRemoved", testThatSingletonIsReleasedWhenDefinitionIsRemoved),
-      ("testThatSingletonIsReleasedWhenDefinitionIsOverridden", testThatSingletonIsReleasedWhenDefinitionIsOverridden),
-      ("testThatSingletonIsReleasedWhenContainerIsReset", testThatSingletonIsReleasedWhenContainerIsReset),
-      ("testThatItReusesInstanceInObjectGraphScopeDuringResolve", testThatItReusesInstanceInObjectGraphScopeDuringResolve),
-      ("testThatItDoesNotReuseInstanceInObjectGraphScopeInNextResolve", testThatItDoesNotReuseInstanceInObjectGraphScopeInNextResolve),
-      ("testThatItDoesNotReuseInstanceInObjectGraphScopeResolvedForNilTag", testThatItDoesNotReuseInstanceInObjectGraphScopeResolvedForNilTag)
-    ]
-  }
-  
-  func setUp() {
-    container.reset()
-  }
-  #else
-  override func setUp() {
-    container.reset()
-  }
-  #endif
-  
-  func testThatPrototypeIsDefaultScope() {
-    let def = container.register { ServiceImp1() as Service }
-    XCTAssertEqual(def.scope, ComponentScope.Prototype)
-  }
-  
-  func testThatScopeCanBeChanged() {
-    let def = container.register(.Singleton) { ServiceImp1() as Service }
-    XCTAssertEqual(def.scope, ComponentScope.Singleton)
-  }
-  
-  func testThatItResolvesTypeAsNewInstanceForPrototypeScope() {
-    //given
-    container.register { ServiceImp1() as Service }
-    
-    //when
-    let service1 = try! container.resolve() as Service
-    let service2 = try! container.resolve() as Service
-    
-    //then
-    XCTAssertFalse(service1 === service2)
-  }
-  
-  func testThatItReusesInstanceForSingletonScope() {
-    //given
-    container.register(.Singleton) { ServiceImp1() as Service }
-    
-    //when
-    let service1 = try! container.resolve() as Service
-    let service2 = try! container.resolve() as Service
-    
-    //then
-    XCTAssertTrue(service1 === service2)
-  }
-  
-  func testThatSingletonIsNotReusedAcrossContainers() {
-    //given
-    let def = container.register(.Singleton) { ServiceImp1() as Service }
-    let secondContainer = DependencyContainer()
-    secondContainer.register(def, forTag: nil)
-    
-    //when
-    let service1 = try! container.resolve() as Service
-    let service2 = try! secondContainer.resolve() as Service
-    
-    //then
-    XCTAssertTrue(service1 !== service2, "Singleton instances should not be reused across containers")
-  }
-  
-  func testThatSingletonIsReleasedWhenDefinitionIsRemoved() {
-    //given
-    let def = container.register(.Singleton) { ServiceImp1() as Service }
-    let service1 = try! container.resolve() as Service
-    
-    //when
-    container.remove(def, forTag: nil)
-    container.register(def, forTag: nil)
-    
-    //then
-    let service2 = try! container.resolve() as Service
-    XCTAssertTrue(service1 !== service2, "Singleton instances should be released when definition is removed from the container")
-  }
-  
-  func testThatSingletonIsReleasedWhenDefinitionIsOverridden() {
-    //given
-    let def = container.register(.Singleton) { ServiceImp1() as Service }
-    let service1 = try! container.resolve() as Service
-    
-    //when
-    container.register(def, forTag: nil)
-    
-    //then
-    let service2 = try! container.resolve() as Service
-    XCTAssertTrue(service1 !== service2, "Singleton instances should be released when definition is overridden")
-  }
-  
-  func testThatSingletonIsReleasedWhenContainerIsReset() {
-    //given
-    let def = container.register(.Singleton) { ServiceImp1() as Service }
-    let service1 = try! container.resolve() as Service
-    
-    //when
-    container.reset()
-    container.register(def, forTag: nil)
-    
-    //then
-    let service2 = try! container.resolve() as Service
-    XCTAssertTrue(service1 !== service2, "Singleton instances should be released when container is reset")
-  }
-  
-  func testThatItReusesInstanceInObjectGraphScopeDuringResolve() {
-    //given
-    container.register(.ObjectGraph) { Client(server: try self.container.resolve()) as Client }
-    
-    container.register(.ObjectGraph) { Server() as Server }.resolveDependencies { container, server in
-      server.client = try container.resolve() as Client
-    }
-    
-    //when
-    let client = try! container.resolve() as Client
-    
-    //then
-    let server = client.server
-    XCTAssertTrue(server.client === client)
-  }
-  
-  func testThatItDoesNotReuseInstanceInObjectGraphScopeInNextResolve() {
-    //given
-    container.register(.ObjectGraph) { Client(server: try self.container.resolve()) as Client }
-    container.register(.ObjectGraph) { Server() as Server }.resolveDependencies { container, server in
-      server.client = try container.resolve() as Client
-    }
-    
-    //when
-    let client = try! container.resolve() as Client
-    let server = client.server
-    
-    let anotherClient = try! container.resolve() as Client
-    let anotherServer = anotherClient.server
-    
-    //then
-    XCTAssertFalse(server === anotherServer)
-    XCTAssertFalse(client === anotherClient)
-  }
-
-  func testThatItDoesNotReuseInstanceInObjectGraphScopeResolvedForNilTag() {
-    //given
-    var service2: Service?
-    container.register(.ObjectGraph) { ServiceImp1() as Service }.resolveDependencies { (c, _) in
-      service2 = try c.resolve(tag: "service") as Service
-      
-      //then
-
-      //when service1 is resolved using this definition due to fallback to nil tag
-      //we don't want every next resolve of service reuse it
-      XCTAssertTrue(service2 is ServiceImp2)
-    }
-    container.register(tag: "service", .ObjectGraph) { ServiceImp2() as Service}
-    
-    //when
-    let service1 = try! container.resolve(tag: "tag") as Service
-
-    //then
-    XCTAssertTrue(service1 is ServiceImp1)
-  }
-
-}
-
@@ -1,333 +0,0 @@
-//
-// Dip
-//
-// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-//
-
-import XCTest
-@testable import Dip
-
-private protocol Service: class { }
-private class ServiceImp1: Service { }
-private class ServiceImp2: Service { }
-
-private protocol Server: class {
-  weak var client: Client? { get }
-}
-private protocol Client: class {
-  var server: Server? { get }
-}
-
-class DipTests: XCTestCase {
-
-  let container = DependencyContainer()
-
-  #if os(Linux)
-  var allTests: [(String, () throws -> Void)] {
-    return [
-      ("testThatItResolvesInstanceRegisteredWithoutTag", testThatItResolvesInstanceRegisteredWithoutTag),
-      ("testThatItResolvesInstanceRegisteredWithTag", testThatItResolvesInstanceRegisteredWithTag),
-      ("testThatItResolvesDifferentInstancesRegisteredForDifferentTags", testThatItResolvesDifferentInstancesRegisteredForDifferentTags),
-      ("testThatNewRegistrationOverridesPreviousRegistration", testThatNewRegistrationOverridesPreviousRegistration),
-      ("testThatItCallsResolveDependenciesOnDefinition", testThatItCallsResolveDependenciesOnDefinition),
-      ("testThatItThrowsErrorIfCanNotFindDefinitionForType", testThatItThrowsErrorIfCanNotFindDefinitionForType),
-      ("testThatItThrowsErrorIfCanNotFindDefinitionForTag", testThatItThrowsErrorIfCanNotFindDefinitionForTag),
-      ("testThatItThrowsErrorIfCanNotFindDefinitionForFactoryWithArguments", testThatItThrowsErrorIfCanNotFindDefinitionForFactoryWithArguments),
-      ("testThatItThrowsErrorIfConstructorThrows", testThatItThrowsErrorIfConstructorThrows),
-      ("testThatItThrowsErrorIfFailsToResolveDependency", testThatItThrowsErrorIfFailsToResolveDependency),
-      ("testThatItCallsDidResolveDependenciesOnResolvableIntance", testThatItCallsDidResolveDependenciesOnResolvableIntance),
-      ("testThatItResolvesCircularDependencies", testThatItResolvesCircularDependencies)
-    ]
-  }
-
-  func setUp() {
-    container.reset()
-  }
-  #else
-  override func setUp() {
-    container.reset()
-  }
-  #endif
-
-  func testThatItResolvesInstanceRegisteredWithoutTag() {
-    //given
-    container.register { ServiceImp1() as Service }
-    
-    //when
-    let serviceInstance = try! container.resolve() as Service
-    
-    //then
-    XCTAssertTrue(serviceInstance is ServiceImp1)
-  }
-
-  func testThatItResolvesInstanceRegisteredWithTag() {
-    //given
-    container.register(tag: "service") { ServiceImp1() as Service }
-    
-    //when
-    let serviceInstance = try! container.resolve(tag: "service") as Service
-    
-    //then
-    XCTAssertTrue(serviceInstance is ServiceImp1)
-  }
-  
-  func testThatItResolvesDifferentInstancesRegisteredForDifferentTags() {
-    //given
-    container.register(tag: "service1") { ServiceImp1() as Service }
-    container.register(tag: "service2") { ServiceImp2() as Service }
-    
-    //when
-    let service1Instance = try! container.resolve(tag: "service1") as Service
-    let service2Instance = try! container.resolve(tag: "service2") as Service
-    
-    //then
-    XCTAssertTrue(service1Instance is ServiceImp1)
-    XCTAssertTrue(service2Instance is ServiceImp2)
-  }
-  
-  func testThatNewRegistrationOverridesPreviousRegistration() {
-    //given
-    container.register { ServiceImp1() as Service }
-    let service1 = try! container.resolve() as Service
-    
-    //when
-    container.register { ServiceImp2() as Service }
-    let service2 = try! container.resolve() as Service
-    
-    //then
-    XCTAssertTrue(service1 is ServiceImp1)
-    XCTAssertTrue(service2 is ServiceImp2)
-  }
-  
-  func testThatItCallsResolveDependenciesOnDefinition() {
-    //given
-    var resolveDependenciesCalled = false
-    container.register { ServiceImp1() as Service }.resolveDependencies { (c, s) in
-      resolveDependenciesCalled = true
-    }
-    
-    //when
-    try! container.resolve() as Service
-    
-    //then
-    XCTAssertTrue(resolveDependenciesCalled)
-  }
-  
-  func testThatItThrowsErrorIfCanNotFindDefinitionForType() {
-    //given
-    container.register { ServiceImp1() as ServiceImp1 }
-    
-    //when
-    AssertThrows(expression: try container.resolve() as Service) { error in
-      guard case let DipError.DefinitionNotFound(key) = error else { return false }
-      
-      //then
-      typealias F = () throws -> Service
-      let expectedKey = DefinitionKey(protocolType: Service.self, factoryType: F.self, associatedTag: nil)
-      XCTAssertEqual(key, expectedKey)
-
-      return true
-    }
-  }
-  
-  func testThatItThrowsErrorIfCanNotFindDefinitionForTag() {
-    //given
-    container.register(tag: "some tag") { ServiceImp1() as Service }
-    
-    //when
-    AssertThrows(expression: try container.resolve(tag: "other tag") as Service) { error in
-      guard case let DipError.DefinitionNotFound(key) = error else { return false }
-      
-      //then
-      typealias F = () throws -> Service
-      let expectedKey = DefinitionKey(protocolType: Service.self, factoryType: F.self, associatedTag: "other tag")
-      XCTAssertEqual(key, expectedKey)
-      
-      return true
-    }
-  }
-  
-  func testThatItThrowsErrorIfCanNotFindDefinitionForFactoryWithArguments() {
-    //given
-    container.register { ServiceImp1() as Service }
-    
-    //when
-    AssertThrows(expression: try container.resolve(withArguments: "some string") as Service) { error in
-      guard case let DipError.DefinitionNotFound(key) = error else { return false }
-      
-      //then
-      typealias F = (String) throws -> Service
-      let expectedKey = DefinitionKey(protocolType: Service.self, factoryType: F.self, associatedTag: nil)
-      XCTAssertEqual(key, expectedKey)
-
-      return true
-    }
-  }
-  
-  func testThatItThrowsErrorIfConstructorThrows() {
-    //given
-    let failedKey = DefinitionKey(protocolType: Any.self, factoryType: Any.self)
-    let expectedError = DipError.DefinitionNotFound(key: failedKey)
-    container.register { () throws -> Service in throw expectedError }
-    
-    //when
-    AssertThrows(expression: try container.resolve() as Service) { error in
-      switch error {
-      case let DipError.DefinitionNotFound(key) where key == failedKey: return true
-      default: return false
-      }
-    }
-  }
-  
-  func testThatItThrowsErrorIfFailsToResolveDependency() {
-    //given
-    let failedKey = DefinitionKey(protocolType: Any.self, factoryType: Any.self)
-    let expectedError = DipError.DefinitionNotFound(key: failedKey)
-    container.register { ServiceImp1() as Service }
-      .resolveDependencies { container, service in
-        //simulate throwing error when resolving dependency
-        throw expectedError
-    }
-    
-    //when
-    AssertThrows(expression: try container.resolve() as Service) { error in
-      switch error {
-      case let DipError.DefinitionNotFound(key) where key == failedKey: return true
-      default: return false
-      }
-    }
-  }
-
-  func testThatItCallsDidResolveDependenciesOnResolvableIntance() {
-    
-    class ResolvableService: Service, Resolvable {
-      var didResolveDependenciesCalled = false
-      
-      func didResolveDependencies() {
-        XCTAssertFalse(didResolveDependenciesCalled, "didResolveDependencies should be called only once per instance")
-        didResolveDependenciesCalled = true
-      }
-    }
-    
-    container.register { ResolvableService() as Service }
-      .resolveDependencies { _, service in
-        XCTAssertFalse((service as! ResolvableService).didResolveDependenciesCalled, "didResolveDependencies should not be called yet")
-        return
-    }
-
-    container.register(tag: "graph", .ObjectGraph) { ResolvableService() as Service }
-      .resolveDependencies { _, service in
-        XCTAssertFalse((service as! ResolvableService).didResolveDependenciesCalled)
-        return
-    }
-
-    container.register(tag: "singleton", .Singleton) { ResolvableService() as Service }
-      .resolveDependencies { _, service in
-        XCTAssertFalse((service as! ResolvableService).didResolveDependenciesCalled)
-        return
-    }
-
-    let service = try! container.resolve() as Service
-    XCTAssertTrue((service as! ResolvableService).didResolveDependenciesCalled)
-
-    let graphService = try! container.resolve(tag: "graph") as Service
-    XCTAssertTrue((graphService as! ResolvableService).didResolveDependenciesCalled)
-    
-    let singletonService = try! container.resolve(tag: "singleton") as Service
-    let _ = try! container.resolve(tag: "singleton") as Service
-    XCTAssertTrue((singletonService as! ResolvableService).didResolveDependenciesCalled)
-  }
-  
-  func testThatItResolvesCircularDependencies() {
-    
-    class ResolvableServer: Server, Resolvable {
-      weak var client: Client?
-      weak var secondClient: Client?
-      
-      init(client: Client) {
-        self.client = client
-      }
-      
-      var didResolveDependenciesCalled = false
-      
-      func didResolveDependencies() {
-        XCTAssertFalse(didResolveDependenciesCalled, "didResolveDependencies should be called only once per instance")
-        didResolveDependenciesCalled = true
-
-        XCTAssertNotNil(self.client)
-        XCTAssertNotNil(self.secondClient)
-        XCTAssertNotNil(self.client?.server)
-        XCTAssertNotNil(self.secondClient)
-        XCTAssertNotNil(self.secondClient?.server)
-      }
-      
-    }
-    
-    class ResolvableClient: Client, Resolvable {
-      var server: Server?
-      var secondServer: Server?
-      
-      init() {}
-      
-      var didResolveDependenciesCalled = false
-      
-      func didResolveDependencies() {
-        XCTAssertFalse(didResolveDependenciesCalled, "didResolveDependencies should be called only once per instance")
-        didResolveDependenciesCalled = true
-
-        XCTAssertNotNil(self.server)
-        XCTAssertNotNil(self.secondServer)
-        XCTAssertNotNil(self.server?.client)
-        XCTAssertNotNil(self.secondServer?.client)
-      }
-      
-    }
-
-    container.register(.ObjectGraph) { try ResolvableServer(client: self.container.resolve()) as Server }
-      .resolveDependencies { (container: DependencyContainer, server: Server) in
-        let server = server as! ResolvableServer
-        server.secondClient = try container.resolve() as Client
-    }
-    
-    container.register(.ObjectGraph) { ResolvableClient() as Client }
-      .resolveDependencies { (container: DependencyContainer, client: Client) in
-        let client = client as! ResolvableClient
-        client.server = try container.resolve() as Server
-        client.secondServer = try container.resolve() as Server
-    }
-
-    let client = (try! container.resolve() as Client) as! ResolvableClient
-    let server = client.server as! ResolvableServer
-    let secondServer = client.secondServer as! ResolvableServer
-    let secondClient = server.secondClient as! ResolvableClient
-    
-    XCTAssertTrue(client === server.client)
-    XCTAssertTrue(client === server.secondClient)
-    XCTAssertTrue(client === secondServer.client)
-    XCTAssertTrue(client === secondServer.secondClient)
-    XCTAssertTrue(client === secondClient)
-    XCTAssertTrue(server === secondServer)
-    
-    XCTAssertTrue(client.didResolveDependenciesCalled)
-    XCTAssertTrue(server.didResolveDependenciesCalled)
-  }
-  
-}
@@ -1,11 +0,0 @@
-import XCTest
-
-XCTMain([
-  DipTests(), 
-  DefinitionTests(), 
-  RuntimeArgumentsTests(), 
-  ComponentScopeTests(),
-  AutoInjectionTests(),
-  ThreadSafetyTests(),
-  AutoWiringTests()
-])
@@ -0,0 +1,2 @@
+[
+]
@@ -1,4 +1,4 @@
-//: [Previous: Shared Instances](@previous)
+//: [Previous: Auto-wiring](@previous)

 import UIKit
 import Dip
@@ -8,7 +8,7 @@ let container = DependencyContainer()

 ### Auto-Injection

-On the previous page you saw how auto-wiring helps us get rid of boilerplate code when registering and resolving components with consturctor injection. Auto-injection solves the same problem for property injection.
+On the previous page you saw how auto-wiring helps us to get rid of boilerplate code when registering and resolving components with consturctor injection. Auto-injection solves the same problem for property injection.

 Let's say you have following related components:
 */
@@ -31,7 +31,7 @@ container.register() { TrackerImp() as Tracker }
 container.register() { LoggerImp() as Logger }

 container.register() { ServiceImp() as Service }
-    .resolveDependencies { container, service in
+    .resolvingProperties { container, service in
        let service = service as! ServiceImp
        service.logger = try container.resolve() as Logger
        service.tracker = try container.resolve() as Tracker
@@ -47,10 +47,10 @@ With auto-injection your code transforms to this:
 */

 class AutoInjectedServiceImp: Service {
-    private var injectedLogger = Injected<Logger>()
+    private let injectedLogger = Injected<Logger>()
    var logger: Logger? { return injectedLogger.value }
    
-    private var injectedTracker = Injected<Tracker>()
+    private let injectedTracker = Injected<Tracker>()
    var tracker: Tracker? { return injectedTracker.value }
 }

@@ -83,9 +83,7 @@ container.register { ServerWithRequiredClient() }
 do {
    let serverWithClient = try container.resolve() as ServerWithRequiredClient
 }
-catch {
-    print(error)
-}
+catch {}

 /*:
 You can make auto-injected property optional by passing `false` to `required` parameter of `Injected<T>`/`InjectedWeak<T>` constructor. For such properties container will ignore any errors when it resolves this property (or any of its dependencies).
@@ -127,12 +125,12 @@ class ServerClientImp: ServerClient {
 The standard way to register such components in `DependencyContainer` will lead to such code:
 */

-container.register(.ObjectGraph) {
+container.register {
    ServerClientImp(server: try container.resolve()) as ServerClient
 }

-container.register(.ObjectGraph) { ServerImp() as Server }
-    .resolveDependencies { (container: DependencyContainer, server: Server) in
+container.register { ServerImp() as Server }
+    .resolvingProperties { (container: DependencyContainer, server: Server) in
        (server as! ServerImp).client = try container.resolve() as ServerClient
 }

@@ -153,8 +151,8 @@ class InjectedClientImp: ServerClient {
    var server: Server? { get { return injectedServer.value } }
 }

-container.register(.ObjectGraph) { InjectedServerImp() as Server }
-container.register(.ObjectGraph) { InjectedClientImp() as ServerClient }
+container.register { InjectedServerImp() as Server }
+container.register { InjectedClientImp() as ServerClient }

 let injectedClient = try! container.resolve() as ServerClient
 injectedClient.server
@@ -176,7 +174,7 @@ class ViewController: UIViewController {
 }

 container.register { ViewController() }
-    .resolveDependencies { container, controller in
+    .resolvingProperties { container, controller in
        controller.logger = try container.resolve() as Logger
        controller.tracker = try container.resolve() as Tracker
        controller.dataProvider = try container.resolve() as DataProvider
@@ -210,4 +208,4 @@ In such scenario when view controller is created by storyboard you will need to
 So as you can see there are certain advantages and disadvatages of using auto-injection. It makes your definitions simpler, especially if there are circular dependencies involved or the number of dependencies is high, removing boilerplate calls to `resolve` method in `resolveDependencies` block of your definitions. But it requires additional properties and some boilerplate code in your implementations, makes your implementatios tightly coupled with Dip. You can avoid tight coupoling by using your own boxing classes instead of `Injected<T>` and `InjectedWeak<T>` (see `AutoInjectedPropertyBox`).
 */

-//: [Next: Testing](@next)
+//: [Next: Type Forwarding](@next)
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -7,7 +7,7 @@ import UIKit

 ### Auto-wiring

-Among three main DI patterns - _constructor_, _property_ and _method_ injection - construction injection should be your choise by default. Dip makes use of this pattern very simple. 
+Among three main DI patterns - _constructor_, _property_ and _method_ injection - constructor injection should be your choise by default. Dip makes using this pattern very simple.

 Let's say you have some VIPER module with following components:
 */
@@ -28,7 +28,7 @@ class View: UIView, ViewOutput {}
 class ServiceImp: Service {}

 /*:
-VIPER module by its nature consists of a lot of components, wired up using protocols. Using construction injection you can end up with following constructors for presenter and interactor:
+VIPER module by its nature consists of a lot of components, wired up using protocols. Using constructor injection you can end up with following constructors for presenter and interactor:
 */

 class InteractorImp: Interactor {
@@ -86,10 +86,10 @@ But then to resolve presenter or interactor you will first need to resolve their
 */

 let service = try! container.resolve() as Service
-let interactor = try! container.resolve(withArguments: service) as Interactor
+let interactor = try! container.resolve(arguments: service) as Interactor
 let view = try! container.resolve() as ViewOutput
 let router = try! container.resolve() as Router
-presenter = try! container.resolve(withArguments: view, interactor, router) as Presenter
+presenter = try! container.resolve(arguments: view, interactor, router) as Presenter
 presenter.interactor.service

 /*:
@@ -109,7 +109,7 @@ You don't need to call `resolve` in a factory and care about order of arguments

 The only requirement is that all constructor arguments should be registered in the container and there should be no several factories with the same _number_ of arguments registered for the same components. 

-In very rare case when you have several different factories with different set of runtime arguments registered for the same component, when you try to resolve it container will try to use these factories one by one until one of them succeeds starting with a factory with most numbers of arguments. If it finds two factories with the same number of arguments it will throw an error.
+In very rare cases when you have several factories for the same component with different set of runtime arguments, when you try to resolve it container will try to use factory registered for the same type and tag (if provided, otherwise registered without tag) and with the maximum number of runtime arguments. If it finds two factories registered for the same type and tag and with the same number but different types of arguments it will throw an error.

 You can use auto-wiring with tags. The tag that you pass to `resolve` method will be used to resolve each of the constructor arguments.
 */
@@ -1,6 +1,7 @@
 //: [Previous: Scopes](@previous)

 import Dip
+import Foundation

 let container = DependencyContainer()

@@ -25,7 +26,7 @@ class NetworkClientImp: NetworkClient {
    init() {}
 }

-class Interactor: NetworkClientDelegate {
+class Interactor: NSObject, NetworkClientDelegate {
    let networkClient: NetworkClient
    init(networkClient: NetworkClient) {
        self.networkClient = networkClient
@@ -43,12 +44,12 @@ It's very important that _at least one_ of them uses property injection, because
 Now you can register those classes in container:
 */

-container.register(.ObjectGraph) {
+container.register {
    Interactor(networkClient: try container.resolve()) as NetworkClientDelegate
 }

-container.register(.ObjectGraph) { NetworkClientImp() as NetworkClient }
-    .resolveDependencies { (container, client) -> () in
+container.register { NetworkClientImp() as NetworkClient }
+    .resolvingProperties { (container, client) -> () in
        client.delegate = try container.resolve() as NetworkClientDelegate
 }

@@ -77,26 +78,26 @@ let networkClient = try! container.resolve() as NetworkClient
 networkClient.delegate // delegate was alread released =(

 /*:
-Note also that we used `.ObjectGraph` scope to register implementations. This is also very important to preserve consistency of objects relationships.
+Note also that we used `.shared` scope to register implementations. This is also very important to preserve consistency of objects relationships.

-If we would have used `.Prototype` scope for both components then container would not reuse instances and we would have an infinite loop:
+If we would have used `.unique` scope for both components then container would not reuse instances and we would have an infinite loop:

 - Each attempt to resolve `NetworkClientDelegate` will create new instance of `Interactor`.
 - It will resolve `NetworkClient` which will create new instance of `NetworkClientImp`.
 - It will try to resolve it's delegate property and that will create new instance of `Interactor`
 - … And so on and so on.

-If we would have used `.Prototype` for one of the components it will lead to the same infinite loop or one of the relationships will be invalid:
+If we would have used `.unique` for one of the components it will lead to the same infinite loop or one of the relationships will be invalid:
 */

 container.reset()

-container.register(.Prototype) {
+container.register(.unique) {
    Interactor(networkClient: try container.resolve()) as NetworkClientDelegate
 }

-container.register(.ObjectGraph) { NetworkClientImp() as NetworkClient }
-    .resolveDependencies { (container, client) -> () in
+container.register { NetworkClientImp() as NetworkClient }
+    .resolvingProperties { (container, client) -> () in
        client.delegate = try container.resolve() as NetworkClientDelegate
 }

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -0,0 +1,71 @@
+//: [Previous: Type Forwarding](@previous)
+
+import Dip
+
+/*:
+ ### Containers collaboration
+
+ Sometimes it makes sence to break your configuration in separate modules. For that you can use containers collaboration. You can link containers with each other and when you try to resolve a type using container where it was not registered, this container will forward request to its collaborating container. This way you can share core configurations or break them in separate modules, for example matching user stories, and still be able to link components from different modules.
+ */
+
+protocol DataStore {}
+class CoreDataStore: DataStore {}
+class AddEventWireframe {
+    var eventsListWireframe: EventsListWireframe?
+}
+class EventsListWireframe {
+    var addEventWireframe: AddEventWireframe?
+    let dataStore: DataStore
+    init(dataStore: DataStore) {
+        self.dataStore = dataStore
+    }
+}
+
+
+let rootContainer = DependencyContainer()
+rootContainer.register(.singleton) { CoreDataStore() as DataStore }
+
+let eventsListModule = DependencyContainer()
+eventsListModule.register { EventsListWireframe(dataStore: $0) }
+    .resolvingProperties { container, wireframe in
+        wireframe.addEventWireframe = try container.resolve()
+}
+
+let addEventModule = DependencyContainer()
+addEventModule.register { AddEventWireframe() }
+
+eventsListModule.collaborate(with: addEventModule, rootContainer)
+
+var eventsListWireframe = try eventsListModule.resolve() as EventsListWireframe
+eventsListWireframe.dataStore
+eventsListWireframe.addEventWireframe
+
+/*:
+ As you can see dependencies were resolved even though not all components were registered in the same container.
+ It is even safe to make circular references between containers. This way you can resolve circular dependencies between components registered in different containers.
+ */
+
+eventsListModule.reset()
+addEventModule.reset()
+
+eventsListModule.register { EventsListWireframe(dataStore: $0) }
+    .resolvingProperties { container, wireframe in
+        wireframe.addEventWireframe = try container.resolve()
+}
+
+addEventModule.register { AddEventWireframe() }
+    .resolvingProperties { container, wireframe in
+        wireframe.eventsListWireframe = try container.resolve()
+}
+
+addEventModule.collaborate(with: eventsListModule)
+
+eventsListWireframe = try eventsListModule.resolve() as EventsListWireframe
+eventsListWireframe.addEventWireframe
+eventsListWireframe.addEventWireframe?.eventsListWireframe === eventsListWireframe
+
+/*:
+ If you try to link container with itself it will be silently ignored. When forwarding request collaborating containers will be iterated in the same order that they were added.
+ */
+
+//: [Next: Testing](@next)
@@ -21,6 +21,9 @@ or using a configuration block:
 */

 container = DependencyContainer { container in
+    //do not forget to use unowned reference if you will need
+    //to reference container inside definition's factory
+    unowned let container = container
    //register components here
 }

@@ -35,7 +35,7 @@ You can use `DependencyContainer.Tag` enum, String or Integer literals, or insta
 */

 container.register(tag: "tag") { ServiceImp1() as Service }
-container.register(tag: .Int(0)) { ServiceImp1() as Service }
+container.register(tag: 0) { ServiceImp1() as Service }

 enum MyCustomTag: String, DependencyTagConvertible {
    case SomeTag
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -1,9 +1,8 @@
 //: [Previous: Registering Components](@previous)

 import Dip
-let container = DependencyContainer { container in
-    container.register { ServiceImp1() as Service }
-}
+let container = DependencyContainer()
+container.register { ServiceImp1() as Service }

 /*:

@@ -42,6 +41,6 @@ let defaultService = try! container.resolve() as Service
 You can use runtime arguments to resolve components. Dip supports up to six arguments. For more details see ["Runtime arguments"](Runtime%20arguments).
 */
 container.register { service in ClientImp1(service: service) as Client }
-let client = try! container.resolve(withArguments: service) as Client
+let client = try! container.resolve(arguments: service) as Client

 //: [Next: Runtime Arguments](@next)
@@ -15,18 +15,15 @@ Note that __types__, __number__ and __order__ of arguments matters and you can r
 container.register { (url: NSURL, port: Int) in ServiceImp4(name: "1", baseURL: url, port: port) as Service }
 container.register { (port: Int, url: NSURL) in ServiceImp4(name: "2", baseURL: url, port: port) as Service }
 container.register { (port: Int, url: NSURL?) in ServiceImp4(name: "3", baseURL: url!, port: port) as Service }
-container.register { (port: Int, url: NSURL!) in ServiceImp4(name: "4", baseURL: url, port: port) as Service }

 let url: NSURL = NSURL(string: "http://example.com")!
-let service1 = try! container.resolve(withArguments: url, 80) as Service
-let service2 = try! container.resolve(withArguments: 80, url) as Service
-let service3 = try! container.resolve(withArguments: 80, NSURL(string: "http://example.com")) as Service
-let service4 = try! container.resolve(withArguments: 80, NSURL(string: "http://example.com")! as NSURL!) as Service
+let service1 = try! container.resolve(arguments: url, 80) as Service
+let service2 = try! container.resolve(arguments: 80, url) as Service
+let service3 = try! container.resolve(arguments: 80, NSURL(string: "http://example.com")) as Service

 (service1 as! ServiceImp4).name
 (service2 as! ServiceImp4).name
 (service3 as! ServiceImp4).name
-(service4 as! ServiceImp4).name

 /*:
 Note that all of the services were resolved using different factories.
@@ -35,12 +32,16 @@ _Dip_ supports up to six runtime arguments. If that is not enougth you can exten
 */

 extension DependencyContainer {
-    public func register<T, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7>(tag tag: Tag? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7) throws -> T> {
-        return registerFactory(tag: tag, scope: scope, factory: factory)
+    
+    @discardableResult
+    public func register<T, A, B, C, D, E, F, G>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping (A, B, C, D, E, F, G) throws -> T) -> Definition<T, (A, B, C, D, E, F, G)> {
+        return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 7) { container, tag in
+            try factory(container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag))
+        }
    }
    
-    public func resolve<T, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7>(tag tag: Tag? = nil, _ arg1: Arg1, _ arg2: Arg2, _ arg3: Arg3, _ arg4: Arg4, _ arg5: Arg5, _ arg6: Arg6, _ arg7: Arg7) throws -> T {
-        return try resolve(tag: tag) { (factory: (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7) throws -> T) in try factory(arg1, arg2, arg3, arg4, arg5, arg6, arg7) }
+    public func resolve<T, A, B, C, D, E, F, G>(tag: DependencyTagConvertible? = nil, _ arg1: A, _ arg2: B, _ arg3: C, _ arg4: D, _ arg5: E, _ arg6: F, _ arg7: G) throws -> T {
+        return try resolve(tag: tag) { factory in try factory(arg1, arg2, arg3, arg4, arg5, arg6, arg7) }
    }
 }

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -8,40 +8,60 @@ let container = DependencyContainer()

 ### Scopes

-Dip supports three different scopes of objects: _Prototype_, _ObjectGraph_ and _Singleton_.
+Dip supports three different scopes of objects: _Unique_, _Shared_ and _Singleton_.

-* The `.Prototype` scope will make the `DependencyContainer` resolve your type as __a new instance every time__ you call `resolve`. This is the default scope.
-* The `.ObjectGraph` scope is like `.Prototype` scope, but it will make the `DependencyContainer` to reuse resolved instances during one (recursive) call to `resolve` method. When this call returns, all resolved instances will be discarded and next call to `resolve` will produce new instances. This scope should be used to resolve [circular dependencies](Circular%20dependencies).
-* The `.Singleton` scope will make the `DependencyContainer` retain the instance once resolved the first time, and reuse it in the next calls to `resolve` during the container lifetime.
+* The `Unique` scope will make the `DependencyContainer` resolve your type as __a new instance every time__ you call `resolve`. This is the default scope.
+* The `Shared` scope is like `Unique` scope, but it will make the `DependencyContainer` to reuse resolved instances during one (recursive) call to `resolve` method. When this call returns, all resolved instances will be discarded and next call to `resolve` will produce new instances. This scope should be used to resolve [circular dependencies](Circular%20dependencies).
+* The `Singleton` scope will make the `DependencyContainer` retain the instance once resolved the first time, and reuse it in the next calls to `resolve` during the container lifetime.
+* The `EagerSingleton` scope is the same as `Singleton` scope but instances with this scope will be created when you call `bootstrap()` method on the container.
+* The `WeakSingleton` scope is the same as `Singleton` scope but instances are stored in container as weak references. This scope can be usefull when you need to recreate object graph without reseting container.

-The `.Prototype` scope is the default. To set a scope you pass it as an argument to `register` method.
+The `Unique` scope is the default. To set a scope you pass it as an argument to `register` method.
 */

 container.register { ServiceImp1() as Service }
-container.register(tag: "prototype", .Prototype) { ServiceImp1() as Service }
-container.register(tag: "object graph", .ObjectGraph) { ServiceImp2() as Service }
-container.register(tag: "shared instance", .Singleton) { ServiceImp3() as Service }
+container.register(.unique, tag: "prototype") { ServiceImp1() as Service }
+container.register(.shared, tag: "object graph") { ServiceImp2() as Service }
+container.register(.singleton, tag: "shared instance") { ServiceImp3() as Service }

 let service = try! container.resolve() as Service
 let anotherService = try! container.resolve() as Service
-// They are different instances as the scope defaults to .Prototype
+// They are different instances as the scope defaults to .unique
 service as! ServiceImp1 === anotherService as! ServiceImp1 // false

 let prototypeService = try! container.resolve(tag: "prototype") as Service
-let anotherPrototypeService = try! container.resolve(tag: "prototype") as Service
+let anotherUniqueService = try! container.resolve(tag: "prototype") as Service
 // They are different instances:
-prototypeService as! ServiceImp1 === anotherPrototypeService as! ServiceImp1 // false
+prototypeService === anotherUniqueService // false

 let graphService = try! container.resolve(tag: "object graph") as Service
 let anotherGraphService = try! container.resolve(tag: "object graph") as Service
-// still different instances — the ObjectGraph scope only keep instances during one (recursive) resolution call,
+// still different instances — the Shared scope only keep instances during one (recursive) resolution call,
 // so the two calls on the two lines above are different calls and use different instances
-graphService as! ServiceImp2 === anotherGraphService as! ServiceImp2 // false
+graphService === anotherGraphService // false

 let sharedService = try! container.resolve(tag: "shared instance") as Service
 let sameSharedService = try! container.resolve(tag: "shared instance") as Service
 // same instances, the singleton scope keep and reuse instances during the lifetime of the container
 sharedService as! ServiceImp3 === sameSharedService as! ServiceImp3

+/*:
+ ### Bootstrapping
+ 
+ You can use `bootstrap()` method to fix your container setup and initialise components registered with `EagerSingleton` scope.
+ After bootstrapping if you try to add or remove any definition it will cause runtime exception. Call `boostrap` when you registered all the components, for example at the end of initialization block if you use `init(configBlock:)`.
+ */
+
+var resolvedEagerSingleton = false
+let definition = container.register(.eagerSingleton, tag: "eager shared instance") { ServiceImp1() as Service }
+    .resolvingProperties { _ in resolvedEagerSingleton = true }
+
+try! container.bootstrap()
+resolvedEagerSingleton
+
+let eagerSharedService = try! container.resolve(tag: "eager shared instance") as Service
+
+container.remove(definition)
+
 //: [Next: Circular Dependencies](@next)

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -33,7 +33,7 @@ class ApiClientSingleton {
 }

 class MyViewControllerWithSingleton: UIViewController {
-  override func viewDidAppear(amimated: Bool) {
+  override func viewDidAppear(_ amimated: Bool) {
    super.viewDidAppear(amimated)
    ApiClientSingleton.sharedInstance.get("/users") { /* refresh your UI */ }
  }
@@ -71,13 +71,13 @@ class MyViewController: UIViewController {
  var apiClient: ApiClientProtocol!
  
  override func viewDidAppear(amimated: Bool) {
-    super.viewDidAppear(amimated)
+    super.viewDidAppear(_ amimated)
    apiClient.get("path") {}
  }
  
  convenience init(apiClient: ApiClientProtocol) {
-    self.init()
    self.apiClient = apiClient
+    self.init()
  }
  
  init() {
@@ -90,7 +90,7 @@ class MyViewController: UIViewController {
 }

 //inject with constructor
-let viewController = MyViewController(apiClient: ApiClient())
+var viewController = MyViewController(apiClient: ApiClient())
 //or with property
 viewController.apiClient = ApiClient()

@@ -98,61 +98,18 @@ viewController.apiClient = ApiClient()
 With Dip this code can look like this:
 */

-let container = DependencyContainer { container in
-    container.register { ApiClient() as ApiClientProtocol }
-}
+let container = DependencyContainer()
+container.register { ApiClient() as ApiClientProtocol }

-class DipViewController: UIViewController {
-    var apiClient: ApiClientProtocol!
-    
-    override func viewDidAppear(amimated: Bool) {
-        super.viewDidAppear(amimated)
-        apiClient.get("path") {}
-    }
-    
-    convenience init(dependencies: DependencyContainer) {
-        self.init()
-        self.apiClient = try! dependencies.resolve() as ApiClientProtocol
-    }
-    
-    init() {
-        super.init(nibName: nil, bundle: nil)
-    }
-    
-    required init?(coder aDecoder: NSCoder) {
-        fatalError("init(coder:) has not been implemented")
-    }
-}
-
-var dipController = DipViewController(dependencies: container)
+//inject with constructor
+viewController = try MyViewController(apiClient: container.resolve())
+//or with property
+viewController.apiClient = try container.resolve()

 /*:
-Of cource `DependencyContainer` should not be a singleton too. Instead, inject it to objects that need to access it. And use a protocol for that. For example if your view controller needs to access API client, it does not need a reference to `DependencyContainer`, it only needs a reference to _something_ that can provide it an API client instance.
-*/
+Of cource `DependencyContainer` should not be a singleton too. There is just no need for that because you never should call `DependencyContainer` from inside of your components. That will make it a [service locator antipattern]((http://blog.ploeh.dk/2010/02/03/ServiceLocatorisanAnti-Pattern/)). You may only call `DependencyContainer` from the _Composition root_ - the place where all the components are configured and wired together.

-protocol ApiClientProvider {
-  func apiClient() -> ApiClientProtocol
-}
-
-extension DependencyContainer: ApiClientProvider {
-  func apiClient() -> ApiClientProtocol {
-    return try! self.resolve() as ApiClientProtocol
-  }
-}
-
-extension DipViewController {
-    convenience init(apiClientProvider: ApiClientProvider) {
-        self.init()
-        self.apiClient = apiClientProvider.apiClient()
-    }
-}
-
-dipController = DipViewController(apiClientProvider: container)
-
-/*:
-This way you also does not depend directly on Dip. Instead you provide a boundary between Dip — that you don't have control of — and your source code. So when something chagnes in Dip, you update only the boundary code.
-
-Dependency Injection is a pattern (more precisely - a set of patterns) as well as a singleton. And any pattern can be abused. DI can be used in a [wrong way]((http://www.loosecouplings.com/2011/01/dependency-injection-using-di-container.html)), container can easily become a [service locator](http://blog.ploeh.dk/2010/02/03/ServiceLocatorisanAnti-Pattern/). You should carefully decide when to use DI, you should not inject everything and everywhere and define a protocol for every single class you use. For every tool there is a right time and the same way as singleton can harm you the same way DI and protocols abuse can make your code unnececerry complex.
+Dependency Injection is a pattern (more precisely - a set of patterns) as well as a singleton. And any pattern can be abused. DI can be used in a [wrong way]((http://www.loosecouplings.com/2011/01/dependency-injection-using-di-container.html)), container can easily become a service locator. You should carefully decide when to use DI, you should not inject everything and everywhere and define a protocol for every single class you use. For every tool there is a right time and the same way as singleton can harm you the same way DI and protocols abuse can make your code unnececerry complex.

 If you want to know more about Dependency Injection in general we recomend you to read ["Dependency Injection in .Net" by Mark Seemann](https://www.manning.com/books/dependency-injection-in-dot-net). Dip was inspired by implementations of IoC container for .Net platform and shares core principles described in that book.

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -1,37 +1,49 @@
-//: [Previous: Shared Instances](@previous)
+//: [Previous: Containers Collaboration](@previous)

+//import XCTest
+import Dip
+
+let container = DependencyContainer()

 /*:

 ### Testing
+ 
+ If you use Dependency Injection patterns like contructor and property injection it will be much easier
+ to unit test your components. When it comes to integration tests you may want to mock some real services.
+ In these tests you can register mock implementation in the container and it will be injected instead of the real implementation.

 Dip is convenient to use for testing. Here is s simple example of how you can write tests with Dip.

-__Note__: That's a very simple example just to demostrate use of Dip in tests, not how you should or should not tests your code in general. 
+> That's a very simple example just to demonstrate use of Dip in tests, not how you should or should not test your code in general.
 You can learn more about testing based on state verification vs behavior verification [here](http://martinfowler.com/articles/mocksArentStubs.html).
-
+ 
+> XCTest is not supported by playgrounds so to be able to compile this page we commented out XCTest specific code.
 */

-protocol Service {
+protocol ServiceType {
    func doSomething()
 }

+class RealService: ServiceType {
+    func doSomething() {
+        //do something real
+    }
+}
+
 class Client {
-    var service: Service!
+    var service: ServiceType!
    
    func callService() {
        service.doSomething()
    }
 }

-import XCTest
-import Dip
-
 /*:
 Instead of the real `Service` implementation, provide a _fake_ implementation with test hooks that you need:
 */

-class FakeService: Service {
+class FakeService: ServiceType {
    var doSomethingCalled = false
    
    func doSomething() {
@@ -41,30 +53,60 @@ class FakeService: Service {
    init() {}
 }

-class MyTests: XCTestCase {
-    var container: DependencyContainer!
-    
-    override func setUp() {
-        super.setUp()
-        
 /*:
-Register fake implementation as `Service`:
+ Somewhere in your production code you register real implementations:
+ */
+func configure(container: DependencyContainer) {
+    container.register { RealService() as ServiceType }
+    container.register { Client() }
+        .resolvingProperties { container, client in
+            client.service = try container.resolve()
+    }
+}
+
+class MyTests/*: XCTestCase*/ {
+    
+    /*override*/ func setUp() {
+        //super.setUp()
+
+/*:
+ Reset container configuration to normal state:
 */
-        container = DependencyContainer { container in
-            container.register { FakeService() as Service }
-        }
+        container.reset()
+        configure(container: container)
    }
    
    func testThatDoSomethingIsCalled() {
-        let sut = Client()
-        sut.service = try! container.resolve() as Service
-
+        /*:
+         Register fake implementation as `Service`:
+         */
+        container.register { FakeService() as ServiceType }
+        
+        let sut = try! container.resolve() as Client
        sut.callService()
        
 /*:
 And finally you test it was called:
 */
-        XCTAssertTrue((sut.service as! FakeService).doSomethingCalled)
+        let service = sut.service as! FakeService
+        //XCTAssertTrue(service.doSomethingCalled)
    }
 }

+/*:
+ You can also validate your container configuration. You can do that either in a separate test suit or when runnging application in `DEBUG` mode.
+ 
+ During validation container will try to resolve all the definitions registered in it. If some of definitions requires runtime arguments you can provide them as arguments to `validate` method. They should exactly match types of arguments required by factories. Multiple arguments for the single factory should be grouped in a tuple. If you don't provide arguments validation will fail.
+ */
+container.register { (url: NSURL, port: Int) in ServiceImp4(name: "1", baseURL: url, port: port) as Service }
+try! container.validate((NSURL(string: "https://github.com/AliSoftware/Dip")!, 80))
+
+do {
+    try container.validate()
+}
+catch {
+    print(error)
+}
+
+
+
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Timeline
-   version = "3.0">
-   <TimelineItems>
-   </TimelineItems>
-</Timeline>
@@ -0,0 +1,110 @@
+//: [Previous: Auto-injection](@previous)
+
+import Foundation
+import Dip
+
+let container = DependencyContainer()
+
+/*:
+### Type Forwarding
+ 
+Very often we end up with single class that implements several protocols. This is normal even in [VIPER architecture](https://github.com/mutualmobile/VIPER-SWIFT/blob/master/VIPER-SWIFT/Classes/Modules/List/User%20Interface/Presenter/ListPresenter.swift#L12) that constantly strives for Single Responsibility Principle.
+ 
+ Let's look at example of VIPER architecture:
+ */
+
+extension ListPresenter: ListInteractorOutput, ListModuleInterface, AddModuleDelegate {}
+extension ListInteractor: ListInteractorInput {}
+extension AddPresenter: AddModuleInterface {}
+
+/*:
+ In VIPER we need to create several objects (presenters, wireframes, interactors) which should be accessed thorugh different interfaces. We need to wire them all together so that we have the same instances in place for different types.
+ 
+ - `ListInteractor` referenced by `ListPresenter` in its `listInteractor` property (via `ListInteractorInput` protocol) should hold a backward reference to the same presenter in its `output` property
+ - `ListWireframe` referenced by `ListPresenter` should also hold a backward reference to the same presenter in its `listPresenter` property
+ - `AddWireframe` should hold a reference to `AddPresenter` that should hold reference to the same `ListPresenter` in its `addModuleDelegate` property (via `AddModuleDelegate` protocol).
+ 
+ We can achieve this result by explicitly rosolving concrete types:
+ */
+
+container.register { ListWireframe(addWireFrame: $0, listPresenter: $1) }
+container.register { AddWireframe(addPresenter: $0) }
+
+var listInteractorDefinition = container.register { ListInteractor() }
+    .resolvingProperties { container, interactor in
+        interactor.output = try container.resolve() as ListPresenter
+}
+
+var listPresenterDefinition = container.register { ListPresenter() }
+    .resolvingProperties { container, presenter in
+        presenter.listInteractor = try container.resolve() as ListInteractor
+        presenter.listWireframe = try container.resolve()
+}
+
+var addPresenterDefinition = container.register { AddPresenter() }
+    .resolvingProperties { container, presenter in
+        presenter.addModuleDelegate = try container.resolve() as ListPresenter
+}
+
+var addPresenter = try! container.resolve() as AddPresenter
+var listPresenter = addPresenter.addModuleDelegate as! ListPresenter
+var listInteractor = listPresenter.listInteractor as! ListInteractor
+listInteractor.output === listPresenter
+var listWireframe = listPresenter.listWireframe
+listWireframe?.listPresenter === listPresenter
+
+/*:
+ Alternatively we can use type-forwarding. With type-forwarding we register definition for one (source) type and also for another (forwarded) type. When container will try to resolve forwarded type it will use the same definition as for source type, and (if registered in `Shared` scope or as a singleton) will reuse the same instance. With that you don't need to resolve concrete types in definitions:
+ */
+
+listInteractorDefinition = container.register { ListInteractor() }
+    .resolvingProperties { container, interactor in
+        interactor.output = try container.resolve()
+}
+
+listPresenterDefinition = container.register { ListPresenter() }
+    .resolvingProperties { container, presenter in
+        presenter.listInteractor = try container.resolve()
+        presenter.listWireframe = try container.resolve()
+}
+
+addPresenterDefinition = container.register { AddPresenter() }
+    .resolvingProperties { container, presenter in
+        presenter.addModuleDelegate = try container.resolve()
+}
+
+/*:
+ And now we register definitions for type-forwarding:
+ */
+listInteractorDefinition
+    .implements(ListInteractorInput.self)
+listPresenterDefinition
+    .implements(ListInteractorOutput.self)
+    .implements(ListModuleInterface.self)
+    .implements(AddModuleDelegate.self)
+
+addPresenter = try! container.resolve() as AddPresenter
+listPresenter = addPresenter.addModuleDelegate as! ListPresenter
+listInteractor = listPresenter.listInteractor as! ListInteractor
+listInteractor.output === listPresenter
+listWireframe = listPresenter.listWireframe
+listWireframe?.listPresenter === listPresenter
+
+/*:
+ Type forwarding will work the same way whenever your resolve dependencies with property injection using `resolveDependencies` block, or with auto-injected properties, or with constructor injection and auto-wiring.
+ 
+ Registering definition for type forwarding will effectively register another definition in the container, linked with original one. So the same overriding rool will be applied for such registrations - last wins. If you need to register different definitions for the same type you should register them with different tags.
+ 
+ You can also provide `resolveDependencies` block for forwarded definition. First container will call `resolveDependencies` block of the source definition, and then of forwarded definition:
+ */
+listInteractorDefinition
+    .resolvingProperties { container, interactor in
+        print("resolved ListInteractor")
+}
+let _ = container.register(listInteractorDefinition, type: ListInteractorInput.self)
+    .resolvingProperties { container, interactor in
+        print("resolved ListInteractorInput")
+}
+addPresenter = try! container.resolve() as AddPresenter
+
+//: [Next: Containers Collaboration](@next)
@@ -0,0 +1 @@
+[]
@@ -1,6 +1,6 @@
 import Foundation

-public protocol Service {}
+public protocol Service: class {}

 public class ServiceImp1: Service {
  public init() {}
@@ -74,5 +74,37 @@ public class DataProviderImp: DataProvider {
    public init() {}
 }

+public protocol ListInteractorOutput: class {}
+public protocol ListModuleInterface: class {}
+public protocol ListInteractorInput: class {}
+public class ListPresenter: NSObject {
+    public var listInteractor : ListInteractorInput?
+    public var listWireframe : ListWireframe?
+    public override init() {}
+}
+public class ListInteractor: NSObject {
+    public var output : ListInteractorOutput?
+    public override init() {}
+}

+public class ListWireframe : NSObject {
+    public let addWireframe: AddWireframe
+    public let listPresenter: ListPresenter
+    public init(addWireFrame: AddWireframe, listPresenter: ListPresenter) {
+        self.addWireframe = addWireFrame
+        self.listPresenter = listPresenter
+    }
+}

+public protocol AddModuleDelegate: class {}
+public protocol AddModuleInterface: class {}
+public class AddWireframe: NSObject {
+    let addPresenter : AddPresenter
+    public init(addPresenter: AddPresenter) {
+        self.addPresenter = addPresenter
+    }
+}
+public class AddPresenter: NSObject {
+    public var addModuleDelegate : AddModuleDelegate?
+    public override init() {}
+}
@@ -11,6 +11,8 @@
        <page name='Shared Instances'/>
        <page name='Auto-wiring'/>
        <page name='Auto-injection'/>
+        <page name='Type Forwarding'/>
+        <page name='Containers Collaboration'/>
        <page name='Testing'/>
    </pages>
 </playground>
@@ -1,10 +1,12 @@
 # Dip

-[![CI Status](http://img.shields.io/travis/AliSoftware/Dip.svg?style=flat)](https://travis-ci.org/AliSoftware/Dip)
+[![CI Status](https://travis-ci.org/AliSoftware/Dip.svg?branch=develop)](https://travis-ci.org/AliSoftware/Dip)
 [![Version](https://img.shields.io/cocoapods/v/Dip.svg?style=flat)](http://cocoapods.org/pods/Dip)
 [![Carthage Compatible](https://img.shields.io/badge/Carthage-compatible-4BC51D.svg?style=flat)](https://github.com/Carthage/Carthage)
 [![License](https://img.shields.io/cocoapods/l/Dip.svg?style=flat)](http://cocoapods.org/pods/Dip)
 [![Platform](https://img.shields.io/cocoapods/p/Dip.svg?style=flat)](http://cocoapods.org/pods/Dip)
+[![Swift Version](https://img.shields.io/badge/Swift-3.0--3.1-F16D39.svg?style=flat)](https://developer.apple.com/swift)
+[![Swift Version](https://img.shields.io/badge/Linux-3.0--3.1-4BC51D.svg?style=flat)](https://developer.apple.com/swift)

 ![Animated Dipping GIF](cinnamon-pretzels-caramel-dipping.gif)  
 _Photo courtesy of [www.kevinandamanda.com](http://www.kevinandamanda.com/recipes/appetizer/homemade-soft-cinnamon-sugar-pretzel-bites-with-salted-caramel-dipping-sauce.html)_
@@ -15,362 +17,187 @@ _Photo courtesy of [www.kevinandamanda.com](http://www.kevinandamanda.com/recipe

 It's aimed to be as simple as possible yet provide rich functionality usual for DI containers on other platforms. It's inspired by `.NET`'s [Unity Container](https://msdn.microsoft.com/library/ff647202.aspx) and other DI containers.

-* You start by creating `let dc = DependencyContainer()` and **register all your dependencies, by associating a `protocol` to a `factory`**.
-* Then you can call `dc.resolve()` to **resolve a `protocol` into an instance of a concrete type** using that `DependencyContainer`.
+* You start by creating `let container = DependencyContainer()` and **registering your dependencies, by associating a _protocol_ or _type_ to a `factory`** using `container.register { MyService() as Service }`.
+* Then you can call `container.resolve() as Service` to **resolve an instance of _protocol_ or _type_** using that `DependencyContainer`.
+* You can easily use Dip along with **Storyboards and Nibs** - checkout **[Dip-UI](https://github.com/AliSoftware/Dip-UI)** extensions. There is also a **[code generator](https://github.com/ilyapuchka/dipgen)** that can help to simplify registering new components.

-This allows you to define the real, concrete types only in one place ([e.g. like this in your app](SampleApp/DipSampleApp/DependencyContainers.swift#L22-L27), and [resetting it in your `setUp` for each Unit Tests](SampleApp/Tests/SWAPIPersonProviderTests.swift#L17-L21)) and then [only work with `protocols` in your code](SampleApp/DipSampleApp/Providers/SWAPIStarshipProvider.swift#L12) (which only define an API contract), without worrying about the real implementation.
+<details>
+<summary>Basic usage</summary>

-> You can easily use Dip along with Storyboards and Nibs - checkout [Dip-UI](https://github.com/AliSoftware/Dip-UI) extensions. 
+```swift
+import Dip

-## Advantages of DI and loose coupling
+@UIApplicationMain
+class AppDelegate: UIResponder, UIApplicationDelegate {
+    
+    // Create the container
+    private let container = DependencyContainer { container in
+    
+        // Register some factory. ServiceImp here implements protocol Service
+        container.register { ServiceImp() as Service }
+    }

-* Define clear API contracts before even thinking about implementation, and make your code loosly coupled with the real implementation.
-* Easily switch between implementations — as long as they respect the same API contact (the `protocol`), making your app modular and scalable.
-* Greatly improve testability, as you can register a real instance in your app but a fake instance in your tests dedicated for testing / mocking the fonctionnality
-* Enable parallel development in your team. You and your teammates can work independently on different parts of the app after you agree on the interfaces.
-* As a bonus get rid of those `sharedInstances` and avoid the singleton pattern at all costs.
+    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { 
+        
+        // Resolve a concrete instance. Container will instantiate new instance of ServiceImp
+        let service = try! container.resolve() as Service
+    
+        ...
+    }
+}
+
+```
+
+</details>
+
+<details>
+<summary>More sophisticated example</summary>
+
+```swift
+import Dip
+
+class AppDelegate: UIResponder, UIApplicationDelegate {
+	private let container = DependencyContainer.configure()
+	...
+}
+
+//CompositionRoot.swift
+import Dip
+import DipUI
+
+extension DependencyContainer {
+
+	static func configure() -> DependencyContainer {
+		return DependencyContainer { container in 
+			unowned let container = container
+			DependencyContainer.uiContainers = [container]
+		
+			container.register(tag: "ViewController") { ViewController() }
+			  .resolvingProperties { container, controller in
+				  controller.animationsFactory = try container.resolve() as AnimatonsFactory
+			}
+    
+			container.register { AuthFormBehaviourImp(apiClient: $0) as AuthFormBehaviour }
+			container.register { container as AnimationsFactory }
+			container.register { view in ShakeAnimationImp(view: view) as ShakeAnimation }
+			container.register { APIClient(baseURL: NSURL(string: "http://localhost:2368")!) as ApiClient }
+		}
+	}
+
+}
+
+extension DependencyContainer: AnimationsFactory { 
+    func shakeAnimation(view: UIView) -> ShakeAnimation {
+        return try! self.resolve(withArguments: view)
+    }
+}
+
+extension ViewController: StoryboardInstantiatable {}
+
+//ViewController.swift
+
+class ViewController {
+    var animationsFactory: AnimationsFactory?
+
+    private let _formBehaviour = Injected<AuthFormBehaviour>()
+    
+    var formBehaviour: AuthFormBehaviour? {
+        return _formBehaviour.value
+    }
+	...
+}
+
+```
+
+</details>
+
+## Documentation & Usage Examples
+
+Dip is completely [documented](http://cocoadocs.org/docsets/Dip/5.0.0/) and comes with a Playground that lets you try all its features and become familiar with API. You can find it in `Dip.xcworkspace`.
+
+> Note: it may happen that you will need to build Dip framework before playground will be able to use it. For that select `Dip` scheme and build for iPhone Simulator.
+
+You can find bunch of usage examples and usfull tips in a [wiki](../../wiki). 
+
+If your are using [VIPER](https://www.objc.io/issues/13-architecture/viper/) architecture - [here](https://github.com/ilyapuchka/VIPER-SWIFT) is VIPER demo app that uses Dip instead of manual dependency injection.
+
+There are also several blog posts that describe how to use Dip and some of its implementation details:
+
+- [IoC container in Swift](http://ilya.puchka.me/ioc-container-in-swift/)
+- [IoC container in Swift. Circular dependencies and auto-injection](http://ilya.puchka.me/ioc-container-in-swift-circular-dependencies-and-auto-injection/)
+- [Dependency injection with Dip](http://ilya.puchka.me/dependency-injecinjection-with-dip/)
+
+File an issue if you have any question. Pull requests are warmly welcome too.


-If you want to know more about Dependency Injection in general we recomend you to read ["Dependency Injection in .Net"](https://www.manning.com/books/dependency-injection-in-dot-net) by Mark Seemann. Dip was inspired particularly by implementations of some DI containers for .Net platform and shares core principles described in that book (even if you are not familiar with .Net platform the prenciples described in that book are platform agnostic).
+## Features
+
+- **[Scopes](../../wiki/scopes)**. Dip supports 5 different scopes (or life cycle strategies): _Unique_, _Shared_, _Singleton_, _EagerSingleton_, _WeakSingleton_;
+- **[Auto-wiring](../../wiki/auto-wiring)** & **[Auto-injection](../../wiki/auto-injection)**. Dip can infer your components' dependencies injected in constructor and automatically resolve them as well as dependencies injected with properties.
+- **[Resolving optionals](../../wiki/resolving-optionals)**. Dip is able to resolve constructor or property dependencies defined as optionals.
+- **[Type forwarding](../../wiki/type-forwarding)**. You can register the same factory to resolve different types implemeted by a single class.
+- **[Circular dependencies](../../wiki/circular-dependencies)**. Dip will be able to resolve circular dependencies if you will follow some simple rules;
+- **[Storyboards integration](../../wiki/storyboards-integration)**. You can easily use Dip along with storyboards and Xibs without ever referencing container in your view controller's code;
+- **[Named definitions](../../wiki/named-definitions)**. You can register different factories for the same protocol or type by registering them with [tags]();
+- **[Runtime arguments](../../wiki/runtime-arguments)**. You can register factories that accept up to 6 runtime arguments (and extend it if you need);
+- **[Easy configuration](../../wiki/containers-collaboration)** & **Code generation**. No complex containers hierarchy, no unneeded functionality. Tired of writing all registrations by hand? There is a [cool code generator](https://github.com/ilyapuchka/dipgen) that will create them for you. The only thing you need is to annotate your code with some comments.
+- **Weakly typed components**. Dip can resolve "weak" types when they are unknown at compile time.
+- **Thread safety**. Registering and resolving components is thread safe;
+- **Helpful error messages and configuration validation**. You can validate your container configuration. If something can not be resolved at runtime Dip throws an error that completely describes the issue;
+

 ## Installation

-Dip is available through [CocoaPods](http://cocoapods.org). To install
-it, simply add the following line to your Podfile:
+Since version 5.0.0 Dip is built with Swift 3.0. You can install Dip using your favorite dependency manager:
+
+<details>
+<summary>CocoaPods</summary>
+
+`pod "Dip"`
+
+To build for Swift 2.3 add this code to the bottom of your Podfile

 ```ruby
-pod "Dip"
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    target.build_configurations.each do |config|
+      config.build_settings['SWIFT_VERSION'] = '2.3'
+    end
+  end
+end
 ```

-If you use _Carthage_ add this line to your Cartfile:
+> You need at least 1.1.0.rc.2 version of CocoaPods.
+
+</details>
+
+<details>
+<summary>Carthage</summary>

 ```
 github "AliSoftware/Dip"
 ```

-If you use [_Swift Package Manager_](https://swift.org/package-manager/) add Dip as dependency to you `Package.swift`:
+To build for Swift 2.3 run Carthage with `--toolchain com.apple.dt.toolchain.Swift_2_3` option.

+</details>
+
+<details>
+<summary>Swift Package Manager</summary>
+
+```swift
+.Package(url: "https://github.com/AliSoftware/Dip", majorVersion: 5, minor: 0)
 ```
-let package = Package(
-  name: "MyPackage",
-  dependencies: [
-    .Package(url: "https://github.com/AliSoftware/Dip.git", "4.3.0")
-  ]
-)
-```
+
+</details>

 ## Running tests

-On OSX you can run tests from Xcode. On Linux you need to have Swift Package Manager installed and use it to build test executable:
-
-```
-cd Dip/DipTests
-swift build
-./.build/debug/DipTests
-```
-
-## Playground
-
-Dip comes with a **Playground** to introduce you to Inversion of Control, Dependency Injection, and how to use Dip in practice.
-
-To play with it, [open `Dip.xcworkspace`](Dip/Dip.xcworkspace), then click on the `DipPlayground` entry in Xcode's Project Navigator and let it be your guide.
-
-_Note: Do not open the `DipPlayground.playground` file directly, as it needs to be part of the workspace to access the Dip framework so that the demo code it contains can work._
-
-The next paragraphs give you an overview of the Usage of _Dip_ directly, but if you're new to Dependency Injection, the Playground is probably a better start.
-
-## Usage
-
-### Register instance factories
-
-First, create a `DependencyContainer` and use it to register instance factories with protocols, using those methods:
-
-* `register() { … as SomeType }` will register provided factory with a given type.
-* if you want to register an concrete implementation for some abstraction (protocol) you need **cast the instance to that protocol type** (e.g. `register { PlistUsersProvider() as UsersListProviderType }`).
-* if you want just to register concrete type in container you may not need a type cast
-
-Typically, to register your dependencies as early as possible in your app life-cycle, you will declare a `let dip: DependencyContainer = { … }()` somewhere, most likely in your `AppDelegate`. In unit tests you may configure container in each test method specifically and then reset it in `tearDown()`.
-
-### Resolve dependencies
-
-* `try resolve() as SomeType` will return a new instance matching the requested type (protocol or concrete type).
-* `resolve()` is a generic method so you need to explicitly specify the return type (using `as` or explicitly providing type of a variable that will hold the resulting value) so that Swift's type inference knows which type you're trying to resolve.
-
-```swift
-container.register { ServiceImp() as Service }
-let service = try! container.resolve() as Service
-```
-
-Ususally you will use _abstractions_ for your dependencies, but container can also resolve concrete types, if you register them. You can use that in cases where abstraction is not really required.
-
-```swift
-container.register { ServiceImp() }
-let service: ServiceImp = try! container.resolve()
-```
-
-
-### Scopes
-
-Dip provides three _scopes_ that you can use to register dependencies:
-
-* The `.Prototype` scope will make the `DependencyContainer` resolve your type as __a new instance every time__ you call `resolve`. It's a default scope.
-* The `.ObjectGraph` scope is like `.Prototype` scope but it will make the `DependencyContainer` to reuse resolved instances during one call to `resolve` method. When this call returns all resolved insances will be discarded and next call to `resolve` will produce new instances. This scope _must_ be used to properly resolve circular dependencies.
-* The `.Singleton` scope will make the `DependencyContainer` retain the instance once resolved the first time, and reuse it in the next calls to `resolve` during the container lifetime.
-
-You specify scope when you register dependency like that:
-
-```swift
-container.register() { ServiceImp() as Service } //.Prototype is a default
-container.register(.ObjectGraph) { ServiceImp() as Service }
-container.register(.Singleton) { ServiceImp() as Service }
-```
-
-
-### Using block-based initialization
-
-When calling the initializer of `DependencyContainer()`, you can pass a block that will be called right after the initialization. This allows you to have a nice syntax to do all your `register(…)` calls in there, instead of having to do them separately.
-
-It may not seem to provide much, but it gets very useful, because instead of having to do setup the container like this:
-
-```swift
-let dip: DependencyContainer = {
-    let dip = DependencyContainer()
-
-    dip.register { ProductionEnvironment(analytics: true) as EnvironmentType }
-    dip.register { WebService() as WebServiceAPI }
-
-    return dip
-    }()
-```
-
-you can instead write this exact equivalent code, which is more compact, and indent better in Xcode (as the final closing brack is properly aligned):
-
-```swift
-let dip = DependencyContainer { dip in
-    dip.register { ProductionEnvironment(analytics: true) as EnvironmentType }
-    dip.register { WebService() as WebServiceAPI }
-}
-```
-
-### Using tags to associate various factories to one type
-
-* If you give a `tag` in the parameter to `register()`, it will associate that instance or factory with this tag, which can be used later during `resolve` (see below).
-* `resolve(tag: tag)` will try to find a factory that match both the requested protocol _and_ the tag. If it doesn't find any, it will fallback to the factory that only match the requested type.
-* The tags can be `StringLiteralType` or `IntegerLiteralType`. That said you can use plain strings or integers as tags.
-
-
-```swift
-enum WebService: String {
-    case Production
-    case Development
-    
-    var tag: DependencyContainer.Tag { return DependencyContainer.Tag.String(self.rawValue) }
-}
-
-let wsDependencies = DependencyContainer() { dip in
-    dip.register(tag: WebService.Production.tag) { URLSessionNetworkLayer(baseURL: "http://prod.myapi.com/api/")! as NetworkLayer }
-    dip.register(tag: WebService.Development.tag) { URLSessionNetworkLayer(baseURL: "http://dev.myapi.com/api/")! as NetworkLayer }
-}
-
-let networkLayer = try! dip.resolve(tag: WebService.PersonWS.tag) as NetworkLayer
-```
-
-### Runtime arguments
-
-You can register factories that accept up to six arguments. When you resolve dependency you can pass those arguments to `resolve()` method and they will be passed to the factory. Note that _number_, _types_ and _order_ of parameters matters (see _Runtime arguments_ page of the Playground).
-
-```swift
-let webServices = DependencyContainer() { webServices in
-	webServices.register { (url: NSURL, port: Int) in WebServiceImp1(url, port: port) as WebServiceAPI }
-}
-
-let service = try! webServices.resolve(withArguments: NSURL(string: "http://example.url")!, 80) as WebServiceAPI
-
-```
-Though Dip provides support for up to six runtime arguments out of the box you can extend that.
-
-### Circular dependencies
-
-_Dip_ supports circular dependencies. For that you need to register your components with `ObjectGraph` scope and use `resolveDependencies` method of `DefinitionOf` returned by `register` method like this:
-
-```swift
-container.register(.ObjectGraph) {
-    ClientImp(server: try container.resolve() as Server) as Client 
-}
-
-container.register(.ObjectGraph) { ServerImp() as Server }
-    .resolveDependencies { container, server in 
-        server.client = try container.resolve() as Client
-    }
-```
-More information about circular dependencies you can find in the Playground.
-
-### Auto-wiring
-
-When you use constructor injection to inject dependencies in your component auto-wiring enables you to resolve it just with one call to `resolve` method without carying about how to resolve all constructor arguments - container will resolve them for you.
-
-```swift
-class PresenterImp: Presenter {
-    init(view: ViewOutput, interactor: Interactor, router: Router) { ... }
-    ...
-}
-
-container.register { RouterImp() as Router }
-container.register { View() as ViewOutput }
-container.register { InteractorImp() as Interactor }
-container.register { PresenterImp(view: $0, interactor: $1, router: $2) as Presenter }
-
-let presenter = try! container.resolve() as Presenter
-```
-
-### Auto-injection
-
-Auto-injection lets your resolve all property dependencies of the instance resolved by container with just one call, also allowing a simpler syntax to register circular dependencies.
-
-```swift
-protocol Server {
-    weak var client: Client? { get }
-}
-
-protocol Client: class {
-    var server: Server? { get }
-}
-
-class ServerImp: Server {
-    private var injectedClient = InjectedWeak<Client>()
-    var client: Client? { return injectedClient.value }
-}
-
-class ClientImp: Client {
-    private var injectedServer = Injected<Server>()
-    var server: Server? { get { return injectedServer.value} }
-}
-
-container.register(.ObjectGraph) { ServerImp() as Server }
-container.register(.ObjectGraph) { ClientImp() as Client }
-
-let client = try! container.resolve() as Client
-
-```
-You can find more use cases for auto-injection in the Playground available in this repository.
-
-> Tip: You can use either `Injected<T>` and `InjectedWeak<T>` wrappers provided by Dip, or your own wrappers (even plain `Box<T>`) that conform to `AutoInjectedPropertyBox` protocol.
-
-### Thread safety
-
-`DependencyContainer` is thread safe, you can register and resolve components from different threads. 
-Still we encourage you to register components in the main thread early in the application lifecycle to prevent race conditions 
-when you try to resolve component from one thread while it was not yet registered in container by another thread.
-
-### Errors
-
-The resolve operation has a potential to fail because you can use the wrong type, factory or a wrong tag. For that reason Dip throws a `DipError` if it fails to resolve a type. Thus when calling `resolve` you need to use a `try` operator. 
-There are very rare use cases when your application can recover from this kind of error. In most of the cases you can use `try!` to cause an exception at runtime if error was thrown or `try?` if a dependency is optional. This way `try!` serves as an additional mark for developers that resolution can fail. 
-Dip also provides helpful descriptions for errors that can occur when you call `resolve`. See the source code documentation to know more about that.
-
-### Concrete Example
-
-Let's say you have some view model that depends on some data provider and web service:
-
-```swift
-struct WebService {
-  let env: EnvironmentType
-  
-  init(env: EnvironmentType) {
-    self.env = env
-  }
-  
-  func sendRequest(path: String, …) {
-    // … use stuff like env.baseURL here
-  }
-}
-
-struct SomeViewModel {
-  let ws: WebServiceType
-  let friendsProvider: FriendsProviderType
-  
-  init(friendsProvider: FriendsProviderType, webService: WebServiceType) {
-    self.friendsProvider = friendsProvider
-    self.ws = webService
-  }
-  
-  func foo() {
-    ws.someMethodDeclaredOnWebServiceType()
-    let friends = friendsProvider.someFriendsProviderTypeMethod()
-    print("friends: \(friends)")
-  }
-}
-```
-
-As you can see we have few layers of dependencies here. All of them together represent _dependency graph_.
-To be able to resolve this graph with Dip we need to make it aware of those types.
-For that we register the dependencies somewhere early in app life cycle (most likely in AppDelegate):
-
-```swift
-let dip: DependencyContainer = {
-    let dip = DependencyContainer()
-    let enableAnalytics = … //i.e. read the setting from plist
-    dip.register(.Singleton) { ProductionEnvironment(analytics: enableAnalytics) as EnvironmentType }
-    dip.register(.Singleton) { WebService(env: try dip.resolve()) as WebServiceType }
-
-    dip.register() { userName in DummyFriendsProvider(user: name) as FriendsProviderType }
-    dip.register(tag: "me") { (_: String) in PlistFriendsProvider(plist: "myfriends") as FriendsProviderType }
-
-    dip.register() { userName in
-      let webService = try dip.resolve() as WebServiceType
-      let friendsProvider = try dip.resolve(tag: userName, withArguments: userName) as 
-      return SomeViewModel(friendsProvider: freindsProvider, webService: webService) 
-    }
-    return dip
-}
-```
-
-> Do the same in your Unit Tests target & test cases, but obviously with different _implementations_ (test doubles) registered.
-
-Then to resolve the graph use `dip.resolve()`, like this:
-
-```swift
-let viewModel = try! dip.resolve(withArguments: userName) as SomeViewModel
-//now you can use view model or pass it to it's consumer
-
-```
-
-This way with just one call to `resolve()` you will have the whole graph of your dependencies resolved and ready to use:
-
-* environmet will be resolved as a singleton instance of `ProductionEnvironment` with enabled analitycs;
-* `ws` will be resolved as a singleton instance of `WebService` and will have it's `env` property set to `ProductionEnvironment`, already resolved (and reatined) by container.
-* `friendsProvider` will be resolved as a new instance each time you create a view model, which will be an instance created via 
-`PlistFriendsProvider(plist: "myfriends")` if `userName` is `me` and created via `DummyFriendsProvider(userName)` for any other 
-`userName` value (because `resolve(tag: userName, withArguments: userName)` will fallback to `resolve(tag: nil, withArguments: userName)` in that case, using 
-the instance factory which was registered without a tag, but will pass `userName` as an argument).
-* view model will be created using `init(friendsProvider:webService:)` with `friendsProvider` and `webService` that have been 
-already resolved by container.
-
-When running your Unit tests target, it may be resolved with other instances, depending on how you registered your dependencies in your Test Case.
-
-> Try to constrain calls to `resolve()` method to one place and try to use one call to `resolve()` to instantiate the whole graph of the dependencies. 
-The same should be applied to dependencies registration - it should be performed with one call and should be done in one place. 
-Don't scatter calls to container all around your code. Using `resolve` inside your implementations will be equal to creating dependencies directly and is actually against DI. Moreover it will drag the dependency on Dip everywhere and will make requirements of your types implicit instead of explicit. 
-Instead you should combine use of container with DI patterns like _Constructor Injection_ and _Property Injection_. Any DI container is just a tool, not a goal.
-You should aplly DI patterns in your code first and only then think about using DI container as a tool to make dependencies management easier. 
-You will find some other advices on how to use the container in the Playground.
-We hope that after reading this README and going through the Playground you will admit the benifits of DI and loose coupling that it enables whether you use Dip or not.
-
-### Complete Example Project
-
-In addition to this Usage overview and to the aforementioned playground, you can also find a complete example in the `SampleApp/DipSampleApp` project provided in this repository.
-
-This sample project is a bit more complex, but closer to real-world applications (even if this sample is all about StarWars!),
-by declaring protocols like `NetworkLayer` which can be resolved to a `URLSessionNetworkLayer` in the real app, but to a dummy
-network layer returning fixture data during the Unit Tests.
-
-This sample uses the Star Wars API provided by swapi.co to fetch Star Wars characters and starships info and display them in TableViews.
-
+On OSX you can run tests from Xcode. On Linux you need to have Swift Package Manager installed and use it to build and run tests using this command: `swift build --clean && swift build && swift test`

 ## Credits

-This library has been created by [**Olivier Halligon**](olivier@halligon.net).  
-I'd also like to thank [**Ilya Puchka**](https://twitter.com/ilyapuchka) for his big contribution to it, as he added a lot of great features to it.
+This library has been created by [**Olivier Halligon**](olivier@halligon.net) and is maintained by [**Ilya Puchka**](https://twitter.com/ilyapuchka).

 **Dip** is available under the **MIT license**. See the `LICENSE` file for more info.

@@ -279,7 +279,7 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0700;
-				LastUpgradeCheck = 0700;
+				LastUpgradeCheck = 0900;
 				ORGANIZATIONNAME = AliSoftware;
 				TargetAttributes = {
 					0990225E1BC123C000E76F43 = {
@@ -414,6 +414,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.alisoftware.DipSampleApp;
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Release;
@@ -426,13 +427,21 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
@@ -460,6 +469,7 @@
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = iphoneos;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -471,13 +481,21 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
@@ -496,6 +514,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 8.3;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
+				SWIFT_VERSION = 4.0;
 				VALIDATE_PRODUCT = YES;
 			};
 			name = Release;
@@ -521,6 +540,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "org.cocoapods.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 			};
 			name = Release;
 		};
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0700"
+   LastUpgradeVersion = "0900"
   version = "1.3">
   <BuildAction
      parallelizeBuildables = "YES"
@@ -40,6 +40,7 @@
      buildConfiguration = "Debug"
      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
      shouldUseLaunchSchemeArgsEnv = "YES"
      codeCoverageEnabled = "YES">
      <Testables>
@@ -70,6 +71,7 @@
      buildConfiguration = "Debug"
      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
      launchStyle = "0"
      useCustomWorkingDirectory = "NO"
      ignoresPersistentStateOnLaunch = "NO"
@@ -16,11 +16,11 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
    
    private let container = DependencyContainer()
    
-    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
+    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]? = nil) -> Bool {
        // Override point for customization after application launch.
        
        //This is a composition root where container is configured and all dependencies are resolved
-        configureContainer(container)
+        configure(container: container)
        
        let personProvider = try! container.resolve() as PersonProviderAPI
        let starshipProvider = try! container.resolve() as StarshipProviderAPI
@@ -12,8 +12,8 @@ protocol BaseCell {
    static var identifier: String { get }
    static var nib: UINib? { get }
    
-    static func register(tableView: UITableView)
-    static func dequeueFromTableView(tableView: UITableView, forIndexPath indexPath: NSIndexPath) -> Self
+    static func register(_ tableView: UITableView)
+    static func dequeueFromTableView(_ tableView: UITableView, forIndexPath indexPath: IndexPath) -> Self
 }

 extension BaseCell where Self : UITableViewCell {
@@ -22,20 +22,20 @@ extension BaseCell where Self : UITableViewCell {
    }
    static var nib: UINib? { return nil }
    
-    static func register(tableView: UITableView) {
+    static func register(_ tableView: UITableView) {
        if let cellNib = self.nib {
-            tableView.registerNib(cellNib, forCellReuseIdentifier: identifier)
+            tableView.register(cellNib, forCellReuseIdentifier: identifier)
        } else {
-            tableView.registerClass(Self.self as AnyClass, forCellReuseIdentifier: identifier)
+            tableView.register(Self.self as AnyClass, forCellReuseIdentifier: identifier)
        }
    }
    
-    static func dequeueFromTableView(tableView: UITableView, forIndexPath indexPath: NSIndexPath) -> Self {
-        return tableView.dequeueReusableCellWithIdentifier(identifier, forIndexPath: indexPath) as! Self
+    static func dequeueFromTableView(_ tableView: UITableView, forIndexPath indexPath: IndexPath) -> Self {
+        return tableView.dequeueReusableCell(withIdentifier: identifier, for: indexPath) as! Self
    }
 }

 protocol FillableCell: BaseCell {
-    typealias ObjectType
+    associatedtype ObjectType
    func fillWithObject(object: ObjectType)
 }
@@ -16,22 +16,22 @@ final class PersonCell : UITableViewCell, FillableCell {
    @IBOutlet weak var hairLabel: UILabel!
    @IBOutlet weak var eyesLabel: UILabel!
    
-    let heightFormatter: NSLengthFormatter = {
-        let f = NSLengthFormatter()
-        f.forPersonHeightUse = true
+    let heightFormatter: LengthFormatter = {
+        let f = LengthFormatter()
+        f.isForPersonHeightUse = true
        return f
        }()
-    let massFormatter: NSMassFormatter = {
-        let f = NSMassFormatter()
-        f.forPersonMassUse = true
+    let massFormatter: MassFormatter = {
+        let f = MassFormatter()
+        f.isForPersonMassUse = true
        return f
    }()
    
-    func fillWithObject(person: Person) {
+    func fillWithObject(object person: Person) {
        nameLabel.text = person.name
        genderImageView.image = person.gender.flatMap { UIImage(named: $0.rawValue) }
-        heightLabel.text = heightFormatter.stringFromValue(Double(person.height), unit: .Centimeter)
-        massLabel.text = massFormatter.stringFromValue(Double(person.mass), unit: .Kilogram)
+        heightLabel.text = heightFormatter.string(fromValue: Double(person.height), unit: .centimeter)
+        massLabel.text = massFormatter.string(fromValue: Double(person.mass), unit: .kilogram)
        hairLabel.text = person.hairColor
        eyesLabel.text = person.eyeColor
    }
@@ -15,13 +15,13 @@ final class StarshipCell : UITableViewCell, FillableCell {
    @IBOutlet weak var crewLabel: UILabel!
    @IBOutlet weak var passengersLabel: UILabel!
    
-    let numberFormatter = NSNumberFormatter()
+    let numberFormatter = NumberFormatter()
    
-    func fillWithObject(starship: Starship) {
+    func fillWithObject(object starship: Starship) {
        nameLabel.text = starship.name
        modelLabel.text = starship.model
        manufacturerLabel.text = starship.manufacturer
-        crewLabel.text = numberFormatter.stringFromNumber(starship.crew)
-        passengersLabel.text = numberFormatter.stringFromNumber(starship.passengers)
+        crewLabel.text = numberFormatter.string(from: NSNumber(integerLiteral: starship.crew))
+        passengersLabel.text = numberFormatter.string(from: NSNumber(integerLiteral: starship.passengers))
    }
 }
@@ -23,17 +23,17 @@ enum DependencyTags: Int, DependencyTagConvertible {
 }

 // MARK: Dependency Container for Providers
-func configureContainer(dip: DependencyContainer) {
+func configure(container dip: DependencyContainer) {
    
    // Register the NetworkLayer, same for everyone here (but we have the ability to register a different one for a specific WebService if we wanted to)
-    dip.register(.Singleton) { URLSessionNetworkLayer(baseURL: "http://swapi.co/api/")! as NetworkLayer }
+    dip.register(.singleton) { URLSessionNetworkLayer(baseURL: "http://swapi.co/api/")! as NetworkLayer }

    if FAKE_PERSONS {
        
        // 1) Register fake persons provider
        //Here we use constructor injection for one of the dependencies property injection for another, and we provide dependencies manually
        dip.register() { FakePersonsProvider(dummyProvider: DummyPilotProvider()) as PersonProviderAPI }
-            .resolveDependencies { (_, resolved: PersonProviderAPI) in
+            .resolvingProperties { (_, resolved: PersonProviderAPI) in
                //here we resolve optional dependencies
                //see what happens when you comment this out
                (resolved as! FakePersonsProvider).plistProvider = PlistPersonProvider(plist: "mainPilot")
@@ -60,7 +60,7 @@ func configureContainer(dip: DependencyContainer) {
        //Here we use constructor injection, but instead of providing dependencies manually container resolves them for us
        dip.register() {
            FakeStarshipProvider(
-                dummyProvider: try dip.resolve(tag: DependencyTags.Dummy, withArguments: "Main Pilot"),
+                dummyProvider: try dip.resolve(tag: DependencyTags.Dummy, arguments: "Main Pilot"),
                hardCodedProvider: try dip.resolve(tag: DependencyTags.Hardcoded)) as StarshipProviderAPI
        }
        
@@ -11,12 +11,12 @@ import Foundation
 ///Provides some dummy Person entities
 struct DummyPilotProvider : PersonProviderAPI {
    
-    func fetchIDs(completion: [Int] -> Void) {
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
        completion(Array(0..<5))
    }
    
-    func fetch(id: Int, completion: Person? -> Void) {
-        completion(dummyPerson(id))
+    func fetch(id: Int, completion: @escaping (Person?) -> Void) {
+        completion(dummyPerson(idx: id))
    }
    
    private func dummyPerson(idx: Int) -> Person {
@@ -40,9 +40,9 @@ class PlistPersonProvider : PersonProviderAPI {
    
    init(plist basename: String) {
        guard
-            let path = NSBundle.mainBundle().pathForResource(basename, ofType: "plist"),
+            let path = Bundle.main.path(forResource: basename, ofType: "plist"),
            let list = NSArray(contentsOfFile: path),
-            peopleDict = list as? [[String:AnyObject]]
+            let peopleDict = list as? [[String:AnyObject]]
            else {
                fatalError("PLIST for \(basename) not found")
        }
@@ -50,11 +50,11 @@ class PlistPersonProvider : PersonProviderAPI {
        self.people = peopleDict.map(PlistPersonProvider.personFromDict)
    }
    
-    func fetchIDs(completion: [Int] -> Void) {
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
        completion(Array(0..<people.count))
    }
    
-    func fetch(id: Int, completion: Person? -> Void) {
+    func fetch(id: Int, completion: @escaping (Person?) -> Void) {
        guard id < people.count else {
            completion(nil)
            return
@@ -65,12 +65,12 @@ class PlistPersonProvider : PersonProviderAPI {
    private static func personFromDict(dict: [String:AnyObject]) -> Person {
        guard
            let name = dict["name"] as? String,
-            height = dict["height"] as? Int,
-            mass = dict["mass"] as? Int,
-            hairColor = dict["hairColor"] as? String,
-            eyeColor = dict["eyeColor"] as? String,
-            genderStr = dict["gender"] as? String,
-            starshipsIDs = dict["starships"] as? [Int]
+            let height = dict["height"] as? Int,
+            let mass = dict["mass"] as? Int,
+            let hairColor = dict["hairColor"] as? String,
+            let eyeColor = dict["eyeColor"] as? String,
+            let genderStr = dict["gender"] as? String,
+            let starshipsIDs = dict["starships"] as? [Int]
            else {
                fatalError("Invalid Plist")
        }
@@ -98,16 +98,16 @@ class FakePersonsProvider: PersonProviderAPI {
        self.dummyProvider = dummyProvider
    }
    
-    func fetchIDs(completion: [Int] -> Void) {
-        dummyProvider.fetchIDs(completion)
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
+        dummyProvider.fetchIDs(completion: completion)
    }
    
-    func fetch(id: Int, completion: Person? -> Void) {
-        if let plistProvider = plistProvider where id == 0 {
-            plistProvider.fetch(id, completion: completion)
+    func fetch(id: Int, completion: @escaping (Person?) -> Void) {
+        if let plistProvider = plistProvider, id == 0 {
+            plistProvider.fetch(id: id, completion: completion)
        }
        else {
-            dummyProvider.fetch(id, completion: completion)
+            dummyProvider.fetch(id: id, completion: completion)
        }
    }

@@ -12,13 +12,13 @@ import Foundation
 struct DummyStarshipProvider : StarshipProviderAPI {
    var pilotName: String
    
-    func fetchIDs(completion: [Int] -> Void) {
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
        let nbShips = pilotName.characters.count
        completion(Array(0..<nbShips))
    }
    
-    func fetch(id: Int, completion: Starship? -> Void) {
-        completion(dummyStarship(id))
+    func fetch(id: Int, completion: @escaping (Starship?) -> Void) {
+        completion(dummyStarship(idx: id))
    }
    
    private func dummyStarship(idx: Int) -> Starship {
@@ -42,11 +42,11 @@ class HardCodedStarshipProvider : StarshipProviderAPI {
        Starship(name: "Third Ship", model: "AwesomeShip Cargo", manufacturer: "HardCoded Inc.", crew: 12, passengers: 150, pilotIDs: [2]),
        ] + Array(4..<75).map { Starship(name: "Ship #\($0)", model: "AwesomeShip Fighter", manufacturer: "HardCoded Inc.", crew: 1, passengers: 2, pilotIDs: [1]) }
    
-    func fetchIDs(completion: [Int] -> Void) {
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
        completion(Array(0..<starships.count))
    }
    
-    func fetch(id: Int, completion: Starship? -> Void) {
+    func fetch(id: Int, completion: @escaping (Starship?) -> Void) {
        guard id < starships.count else {
            completion(nil)
            return
@@ -66,16 +66,16 @@ class FakeStarshipProvider: StarshipProviderAPI {
        self.hardCodedProvider = hardCodedProvider
    }
    
-    func fetchIDs(completion: [Int] -> Void) {
-        hardCodedProvider.fetchIDs(completion)
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
+        hardCodedProvider.fetchIDs(completion: completion)
    }
    
-    func fetch(id: Int, completion: Starship? -> Void) {
+    func fetch(id: Int, completion: @escaping (Starship?) -> Void) {
        if id == 0 {
-            dummyProvider.fetch(id, completion: completion)
+            dummyProvider.fetch(id: id, completion: completion)
        }
        else {
-            hardCodedProvider.fetch(id, completion: completion)
+            hardCodedProvider.fetch(id: id, completion: completion)
        }
    }
    
@@ -9,21 +9,21 @@
 import Foundation

 enum NetworkResponse {
-    case Success(NSData, NSHTTPURLResponse)
+    case Success(Data, HTTPURLResponse)
    case Error(NSError)
    
-    func unwrap() throws -> (NSData, NSHTTPURLResponse) {
+    func unwrap() throws -> (Data, HTTPURLResponse) {
        switch self {
-        case Success(let data, let response):
+        case .Success(let data, let response):
            return (data, response)
-        case Error(let error):
+        case .Error(let error):
            throw error
        }
    }
    
    func json<T>() throws -> T {
        let (data, _) = try self.unwrap()
-        let obj = try NSJSONSerialization.JSONObjectWithData(data, options: [])
+        let obj = try JSONSerialization.jsonObject(with: data, options: [])
        guard let json = obj as? T else {
            throw SWAPIError.InvalidJSON
        }
@@ -32,5 +32,5 @@ enum NetworkResponse {
 }

 protocol NetworkLayer {
-    func request(path: String, completion: NetworkResponse -> Void)
+    func request(path: String, completion: @escaping (NetworkResponse) -> Void)
 }
@@ -9,6 +9,6 @@
 import Foundation

 protocol PersonProviderAPI {
-    func fetchIDs(completion: [Int] -> Void)
-    func fetch(id: Int, completion: Person? -> Void)
+    func fetchIDs(completion: @escaping ([Int]) -> Void)
+    func fetch(id: Int, completion: @escaping (Person?) -> Void)
 }
@@ -9,7 +9,7 @@
 import Foundation
 import Dip

-enum SWAPIError: ErrorType {
+enum SWAPIError: Error {
    case InvalidJSON
 }

@@ -20,8 +20,8 @@ struct SWAPIPersonProvider : PersonProviderAPI {
        self.ws = webService
    }
    
-    func fetchIDs(completion: [Int] -> Void) {
-        ws.request("people") { response in
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
+        ws.request(path: "people") { response in
            do {
                let dict = try response.json() as NSDictionary
                guard let results = dict["results"] as? [NSDictionary] else { throw SWAPIError.InvalidJSON }
@@ -38,14 +38,14 @@ struct SWAPIPersonProvider : PersonProviderAPI {
        }
    }
    
-    func fetch(id: Int, completion: Person? -> Void) {
-        ws.request("people/\(id)") { response in
+    func fetch(id: Int, completion: @escaping (Person?) -> Void) {
+        ws.request(path: "people/\(id)") { response in
            do {
                let json = try response.json() as NSDictionary
                guard
                    let name = json["name"] as? String,
-                    let heightStr = json["height"] as? String, height = Int(heightStr),
-                    let massStr = json["mass"] as? String, mass = Int(massStr),
+                    let heightStr = json["height"] as? String, let height = Int(heightStr),
+                    let massStr = json["mass"] as? String, let mass = Int(massStr),
                    let hairColor = json["hair_color"] as? String,
                    let eyeColor = json["eye_color"] as? String,
                    let gender = json["gender"] as? String,
@@ -20,8 +20,8 @@ struct SWAPIStarshipProvider : StarshipProviderAPI {
        self.ws = webService
    }
    
-    func fetchIDs(completion: [Int] -> Void) {
-        ws.request("starships") { response in
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
+        ws.request(path: "starships") { response in
            do {
                let dict = try response.json() as NSDictionary
                guard let results = dict["results"] as? [NSDictionary] else { throw SWAPIError.InvalidJSON }
@@ -38,16 +38,16 @@ struct SWAPIStarshipProvider : StarshipProviderAPI {
        }
    }
    
-    func fetch(id: Int, completion: Starship? -> Void) {
-        ws.request("starships/\(id)") { response in
+    func fetch(id: Int, completion: @escaping (Starship?) -> Void) {
+        ws.request(path: "starships/\(id)") { response in
            do {
                let json = try response.json() as NSDictionary
                guard
                    let name = json["name"] as? String,
                    let model = json["model"] as? String,
                    let manufacturer = json["manufacturer"] as? String,
-                    let crewStr = json["crew"] as? String, crew = Int(crewStr),
-                    let passengersStr = json["passengers"] as? String, passengers = Int(passengersStr),
+                    let crewStr = json["crew"] as? String, let crew = Int(crewStr),
+                    let passengersStr = json["passengers"] as? String, let passengers = Int(passengersStr),
                    let pilotIDStrings = json["pilots"] as? [String]
                    else {
                        throw SWAPIError.InvalidJSON
@@ -9,6 +9,6 @@
 import Foundation

 protocol StarshipProviderAPI {
-    func fetchIDs(completion: [Int] -> Void)
-    func fetch(id: Int, completion: Starship? -> Void)
+    func fetchIDs(completion: @escaping ([Int]) -> Void)
+    func fetch(id: Int, completion: @escaping (Starship?) -> Void)
 }
@@ -10,33 +10,33 @@ import Foundation

 ///NetworkLayer implementation on top of NSURLSession
 struct URLSessionNetworkLayer : NetworkLayer {
-    let baseURL: NSURL
-    let session: NSURLSession
-    let responseQueue: dispatch_queue_t
+    let baseURL: URL
+    let session: URLSession
+    let responseQueue: DispatchQueue
    
-    init?(baseURL: String, session: NSURLSession = .sharedSession(), responseQueue: dispatch_queue_t = dispatch_get_main_queue()) {
-        guard let url = NSURL(string: baseURL) else { return nil }
+    init?(baseURL: String, session: URLSession = URLSession.shared, responseQueue: DispatchQueue = DispatchQueue.main) {
+        guard let url = URL(string: baseURL) else { return nil }
        self.init(baseURL: url, session: session)
    }
    
-    init(baseURL: NSURL, session: NSURLSession = .sharedSession(), responseQueue: dispatch_queue_t = dispatch_get_main_queue()) {
+    init(baseURL: URL, session: URLSession = URLSession.shared, responseQueue: DispatchQueue = DispatchQueue.main) {
        self.baseURL = baseURL
        self.session = session
        self.responseQueue = responseQueue
    }
    
-    func request(path: String, completion: NetworkResponse -> Void) {
-        let url = self.baseURL.URLByAppendingPathComponent(path)
-        let task = session.dataTaskWithURL(url) { data, response, error in
-            if let data = data, let response = response as? NSHTTPURLResponse {
-                dispatch_async(self.responseQueue) {
+    func request(path: String, completion: @escaping (NetworkResponse) -> Void) {
+        let url = self.baseURL.appendingPathComponent(path)
+        let task = session.dataTask(with: url) { data, response, error in
+            if let data = data, let response = response as? HTTPURLResponse {
+                self.responseQueue.async() {
                    completion(NetworkResponse.Success(data, response))
                }
            }
            else {
-                let err = error ?? NSError(domain: NSURLErrorDomain, code: NSURLError.Unknown.rawValue, userInfo: nil)
-                dispatch_async(self.responseQueue) {
-                    completion(NetworkResponse.Error(err))
+                let err = error ?? NSError(domain: NSURLErrorDomain, code: URLError.unknown.rawValue, userInfo: nil)
+                self.responseQueue.async() {
+                    completion(NetworkResponse.Error(err as NSError))
                }
            }
        }
@@ -21,7 +21,7 @@ extension StoryboardScene where Self.RawValue == String {
    }

    func viewController() -> UIViewController {
-        return Self.storyboard().instantiateViewControllerWithIdentifier(self.rawValue)
+        return Self.storyboard().instantiateViewController(withIdentifier: self.rawValue)
    }
    static func viewController(identifier: Self) -> UIViewController {
        return identifier.viewController()
@@ -9,13 +9,13 @@
 import UIKit

 protocol FetchableTrait: class {
-    typealias ObjectType
+    associatedtype ObjectType
    var objects: [ObjectType]? { get set }
    var batchRequestID: Int { get set }
    var tableView: UITableView! { get }
    
-    func fetchIDs(completion: [Int] -> Void)
-    func fetchOne(id: Int, completion: ObjectType? -> Void)
+    func fetchIDs(completion: @escaping ([Int]) -> Void)
+    func fetchOne(id: Int, completion: @escaping (ObjectType?) -> Void)
    var fetchProgress: (current: Int, total: Int?) { get set }
 }

@@ -27,10 +27,10 @@ extension FetchableTrait {
        objects?.removeAll()
        fetchProgress = (0,objectIDs.count)
        for objectID in objectIDs {
-            fetchOne(objectID) { (object: ObjectType?) in
+            fetchOne(id: objectID) { (object: ObjectType?) in
                // Exit if we failed to retrive an object for this ID, or if the request
                // should be ignored because a new batch request has been started since
-                guard let object = object where batch == self.batchRequestID else { return }
+                guard let object = object, batch == self.batchRequestID else { return }

                if self.objects == nil { self.objects = [] }
                self.objects?.append(object)
@@ -46,7 +46,7 @@ extension FetchableTrait {
        fetchProgress = (0, nil)
        fetchIDs() { objectIDs in
            guard batch == self.batchRequestID else { return }
-            self.loadObjects(objectIDs)
+            self.loadObjects(objectIDs: objectIDs)
        }
    }
    
@@ -63,8 +63,8 @@ extension FetchableTrait {
        }
        let label = UILabel(frame: CGRect(x: 0, y: 0, width: 0, height: 0))
        label.text = text
-        label.textColor = .grayColor()
-        label.font = .systemFontOfSize(12)
+        label.textColor = .gray
+        label.font = UIFont.systemFont(ofSize: 12)
        label.sizeToFit()
        navigationItem.rightBarButtonItem = UIBarButtonItem(customView: label)
    }
@@ -14,45 +14,46 @@ class PersonListViewController: UITableViewController, FetchableTrait {
    
    var personProvider: PersonProviderAPI!
    var starshipProvider: StarshipProviderAPI!
-        
-    func fetchIDs(completion: [Int] -> Void) {
-        return personProvider.fetchIDs(completion)
+    
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
+        return personProvider.fetchIDs(completion: completion)
    }
    
-    func fetchOne(personID: Int, completion: Person? -> Void) {
-        return personProvider.fetch(personID, completion: completion)
+    func fetchOne(id personID: Int, completion: @escaping (Person?) -> Void) {
+        return personProvider.fetch(id: personID, completion: completion)
    }
    
    var fetchProgress: (current: Int, total: Int?) = (0, nil) {
        didSet {
-            displayProgressInNavBar(self.navigationItem)
+            displayProgressInNavBar(navigationItem: self.navigationItem)
        }
    }

-    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
+    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        guard
-            let id = segue.identifier, segueID = UIStoryboard.Segue.Main(rawValue: id)
-            where segueID == .StarshipsSegue,
+            let id = segue.identifier,
+            let segueID = UIStoryboard.Segue.Main(rawValue: id),
+            segueID == .StarshipsSegue,
            let indexPath = self.tableView.indexPathForSelectedRow,
-            let destVC = segue.destinationViewController as? StarshipListViewController,
+            let destVC = segue.destination as? StarshipListViewController,
            let person = self.objects?[indexPath.row]
            else {
                fatalError()
        }
        destVC.starshipProvider = starshipProvider
-        destVC.loadObjects(person.starshipIDs)
+        destVC.loadObjects(objectIDs: person.starshipIDs)
    }
 }

 extension PersonListViewController {
-    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
+    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return objects?.count ?? 0
    }
    
-    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
+    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        guard let object = self.objects?[indexPath.row] else { fatalError() }
        let cell = PersonCell.dequeueFromTableView(tableView, forIndexPath: indexPath)
-        cell.fillWithObject(object)
+        cell.fillWithObject(object: object)
        return cell
    }
 }
@@ -16,44 +16,45 @@ class StarshipListViewController : UITableViewController, FetchableTrait {
    var starshipProvider: StarshipProviderAPI!
    var personProvider: PersonProviderAPI!
    
-    func fetchIDs(completion: [Int] -> Void) {
-        starshipProvider.fetchIDs(completion)
+    func fetchIDs(completion: @escaping ([Int]) -> Void) {
+        starshipProvider.fetchIDs(completion: completion)
    }
-    func fetchOne(shipID:Int, completion: Starship? -> Void) {
-        starshipProvider.fetch(shipID, completion: completion)
+    func fetchOne(id shipID:Int, completion: @escaping (Starship?) -> Void) {
+        starshipProvider.fetch(id: shipID, completion: completion)
    }
    
    var fetchProgress: (current: Int, total: Int?) = (0, nil) {
        didSet {
-            displayProgressInNavBar(self.navigationItem)
+            displayProgressInNavBar(navigationItem: self.navigationItem)
        }
    }
    
-    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
+    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        guard
-            let id = segue.identifier, segueID = UIStoryboard.Segue.Main(rawValue: id)
-            where segueID == .PilotsSegue,
+            let id = segue.identifier,
+            let segueID = UIStoryboard.Segue.Main(rawValue: id),
+            segueID == .PilotsSegue,
            let indexPath = self.tableView.indexPathForSelectedRow,
-            let destVC = segue.destinationViewController as? PersonListViewController,
+            let destVC = segue.destination as? PersonListViewController,
            let starship = self.objects?[indexPath.row]
            else {
                fatalError()
        }
        
        destVC.personProvider = personProvider
-        destVC.loadObjects(starship.pilotIDs)
+        destVC.loadObjects(objectIDs: starship.pilotIDs)
    }
 }

 extension StarshipListViewController {
-    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
+    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return objects?.count ?? 0
    }
    
-    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
+    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        guard let object = self.objects?[indexPath.row] else { fatalError() }
        let cell = StarshipCell.dequeueFromTableView(tableView, forIndexPath: indexPath)
-        cell.fillWithObject(object)
+        cell.fillWithObject(object: object)
        return cell
    }
 }
@@ -14,24 +14,24 @@ var wsDependencies = DependencyContainer()
 // MARK: - Mock object used for tests

 struct NetworkMock : NetworkLayer {
-    let fakeData: NSData?
+    let fakeData: Data?
    
-    init(json: AnyObject) {
+    init(json: Any) {
        do {
-            fakeData = try NSJSONSerialization.dataWithJSONObject(json, options: [])
+            fakeData = try JSONSerialization.data(withJSONObject: json, options: [])
        } catch {
            fakeData = nil
        }
    }
    
-    func request(path: String, completion: NetworkResponse -> Void) {
-        let fakeURL = NSURL(string: "stub://")!.URLByAppendingPathComponent(path)
+    func request(path: String, completion: @escaping (NetworkResponse) -> Void) {
+        let fakeURL = NSURL(string: "http://stub")?.appendingPathComponent(path)
        if let data = fakeData {
-            let response = NSHTTPURLResponse(URL: fakeURL, statusCode: 200, HTTPVersion: "1.1", headerFields:nil)!
+            let response = HTTPURLResponse(url: fakeURL!, statusCode: 200, httpVersion: "1.1", headerFields:nil)!
            completion(.Success(data, response))
        } else {
-            let response = NSHTTPURLResponse(URL: fakeURL, statusCode: 204, HTTPVersion: "1.1", headerFields:nil)!
-            completion(.Success(NSData(), response))
+            let response = HTTPURLResponse(url: fakeURL!, statusCode: 204, httpVersion: "1.1", headerFields:nil)!
+            completion(.Success(Data(), response))
        }
    }
 }
@@ -10,10 +10,10 @@ import XCTest
 import Dip

 class SWAPIPersonProviderTests: XCTestCase {
-    let fakePerson1 = ["name": "John Doe", "mass": "72", "height": "172", "eye_color": "brown", "hair_color": "black", "gender": "male",
-        "starships": ["stub://starship/7/", "stub://starship/15"], "url": "stub://people/1"]
-    let fakePerson2 = ["name": "Jane Doe", "mass": "63", "height": "167", "eye_color": "blue", "hair_color": "red", "gender": "female",
-        "starships": ["stub://starship/11/"], "url": "stub://people/12"]
+    let fakePerson1: [String : Any] = ["name": "John Doe", "mass": "72", "height": "172", "eye_color": "brown", "hair_color": "black", "gender": "male",
+        "starships": ["http://starship/7/", "http://starship/15"], "url": "http://people/1"]
+    let fakePerson2: [String: Any] = ["name": "Jane Doe", "mass": "63", "height": "167", "eye_color": "blue", "hair_color": "red", "gender": "female",
+        "starships": ["http://starship/11/"], "url": "http://people/12"]
    
    override func setUp() {
        super.setUp()
@@ -23,7 +23,7 @@ class SWAPIPersonProviderTests: XCTestCase {
    
    func testFetchPersonIDs() {
        let mock = NetworkMock(json: ["results": [fakePerson1, fakePerson2]])
-        wsDependencies.register(.Singleton) { mock as NetworkLayer }
+        wsDependencies.register(.singleton) { mock as NetworkLayer }
        
        let provider = SWAPIPersonProvider(webService: try! wsDependencies.resolve())
        provider.fetchIDs { personIDs in
@@ -37,10 +37,10 @@ class SWAPIPersonProviderTests: XCTestCase {
    
    func testFetchOnePerson() {
        let mock = NetworkMock(json: fakePerson1)
-        wsDependencies.register(.Singleton) { mock as NetworkLayer }
+        wsDependencies.register(.singleton) { mock as NetworkLayer }
        
        let provider = SWAPIPersonProvider(webService: try! wsDependencies.resolve())
-        provider.fetch(1) { person in
+        provider.fetch(id: 1) { person in
            XCTAssertNotNil(person)
            XCTAssertEqual(person?.name, "John Doe")
            XCTAssertEqual(person?.mass, 72)
@@ -57,10 +57,10 @@ class SWAPIPersonProviderTests: XCTestCase {
    func testFetchInvalidPerson() {
        let json = ["error":"whoops"]
        let mock = NetworkMock(json: json)
-        wsDependencies.register(.Singleton) { mock as NetworkLayer }
+        wsDependencies.register(.singleton) { mock as NetworkLayer }
        
        let provider = SWAPIPersonProvider(webService: try! wsDependencies.resolve())
-        provider.fetch(12) { person in
+        provider.fetch(id: 12) { person in
            XCTAssertNil(person)
        }
    }
@@ -10,10 +10,10 @@ import XCTest
 import Dip

 class SWAPIStarshipProviderTests: XCTestCase {
-    let fakeShip1 = ["name": "Falcon", "model": "Fighter", "manufacturer": "Fake Industries", "crew": "7", "passengers": "15",
-        "pilots": ["stub://people/1/", "stub://people/9"], "url": "stub://starship/4"]
-    let fakeShip2 = ["name": "Voyager", "model": "Cargo", "manufacturer": "Fake Industries", "crew": "18", "passengers": "150",
-        "pilots": ["stub://people/2/", "stub://people/3"], "url": "stub://starship/31"]
+    let fakeShip1: [String: Any] = ["name": "Falcon", "model": "Fighter", "manufacturer": "Fake Industries", "crew": "7", "passengers": "15",
+        "pilots": ["http://people/1/", "http://people/9"], "url": "http://starship/4"]
+    let fakeShip2: [String: Any] = ["name": "Voyager", "model": "Cargo", "manufacturer": "Fake Industries", "crew": "18", "passengers": "150",
+        "pilots": ["http://people/2/", "http://people/3"], "url": "http://starship/31"]
    
    override func setUp() {
        super.setUp()
@@ -23,7 +23,7 @@ class SWAPIStarshipProviderTests: XCTestCase {
    
    func testFetchStarshipIDs() {
        let mock = NetworkMock(json: ["results": [fakeShip1, fakeShip2]])
-        wsDependencies.register(.Singleton) { mock as NetworkLayer }
+        wsDependencies.register(.singleton) { mock as NetworkLayer }
        
        let provider = SWAPIStarshipProvider(webService: try! wsDependencies.resolve())
        provider.fetchIDs { shipIDs in
@@ -38,10 +38,10 @@ class SWAPIStarshipProviderTests: XCTestCase {
    func testFetchOneStarship() {
        
        let mock = NetworkMock(json: fakeShip1)
-        wsDependencies.register(.Singleton) { mock as NetworkLayer }
+        wsDependencies.register(.singleton) { mock as NetworkLayer }
        
        let provider = SWAPIStarshipProvider(webService: try! wsDependencies.resolve())
-        provider.fetch(1) { starship in
+        provider.fetch(id: 1) { starship in
            XCTAssertNotNil(starship)
            XCTAssertEqual(starship?.name, "Falcon")
            XCTAssertEqual(starship?.model, "Fighter")
@@ -57,10 +57,10 @@ class SWAPIStarshipProviderTests: XCTestCase {
    func testFetchInvalidStarship() {
        let json = ["error":"whoops"]
        let mock = NetworkMock(json: json)
-        wsDependencies.register(.Singleton) { mock as NetworkLayer }
+        wsDependencies.register(.singleton) { mock as NetworkLayer }
        
        let provider = SWAPIStarshipProvider(webService: try! wsDependencies.resolve())
-        provider.fetch(12) { starship in
+        provider.fetch(id: 12) { starship in
            XCTAssertNil(starship)
        }
    }
@@ -27,19 +27,31 @@ extension DependencyContainer {
  /**
   Resolves properties of passed object wrapped with `Injected<T>` or `InjectedWeak<T>`
   */
-  func autoInjectProperties(instance: Any) throws {
-    try Mirror(reflecting: instance).children.forEach(_resolveChild)
+  func autoInjectProperties(in instance: Any) throws {
+    let mirror = Mirror(reflecting: instance)
+    
+    //mirror only contains class own properties
+    //so we need to walk through super class mirrors
+    //to resolve super class auto-injected properties
+    var superClassMirror = mirror.superclassMirror
+    while superClassMirror != nil {
+      try superClassMirror?.children.forEach(resolveChild)
+      superClassMirror = superClassMirror?.superclassMirror
+    }
+    
+    try mirror.children.forEach(resolveChild)
  }
  
-  private func _resolveChild(child: Mirror.Child) throws {
+  private func resolveChild(child: Mirror.Child) throws {
+    //HOTFIX for https://bugs.swift.org/browse/SR-2282
+    guard !String(describing: type(of: child.value)).has(prefix: "ImplicitlyUnwrappedOptional") else { return }
    guard let injectedPropertyBox = child.value as? AutoInjectedPropertyBox else { return }
    
-    do {
+    let wrappedType = type(of: injectedPropertyBox).wrappedType
+    let contextKey = DefinitionKey(type: wrappedType, typeOfArguments: Void.self, tag: context.tag)
+    try inContext(key:contextKey, injectedInType: context?.resolvingType, injectedInProperty: child.label, logErrors: false) {
      try injectedPropertyBox.resolve(self)
    }
-    catch {
-      throw DipError.AutoInjectionFailed(label: child.label, type: injectedPropertyBox.dynamicType.wrappedType, underlyingError: error)
-    }
  }
  
 }
@@ -49,6 +61,7 @@ extension DependencyContainer {
 instead of using `Injected<T>` or `InjectedWeak<T>` types.
 
 **Example**:
+ 
 ```swift
 class MyCustomBox<T> {
   private(set) var value: T?
@@ -75,9 +88,9 @@ public protocol AutoInjectedPropertyBox: class {
   
   - parameter container: A container to be used to resolve an instance
   
-  -note: This method is not intended to be called manually, `DependencyContainer` will call it by itself.
+   - note: This method is not intended to be called manually, `DependencyContainer` will call it by itself.
   */
-  func resolve(container: DependencyContainer) throws
+  func resolve(_ container: DependencyContainer) throws
 }

 /**
@@ -93,44 +106,62 @@ public protocol AutoInjectedPropertyBox: class {
 class ClientImp: Client {
   var service = Injected<Service>()
 }
-
 ```
 - seealso: `InjectedWeak`

 */
 public final class Injected<T>: _InjectedPropertyBox<T>, AutoInjectedPropertyBox {
  
+  ///The type of wrapped property.
  public static var wrappedType: Any.Type {
    return T.self
  }

  ///Wrapped value.
-  public private(set) var value: T? {
+  public internal(set) var value: T? {
    didSet {
      if let value = value { didInject(value) }
    }
  }

+  init(value: T?, required: Bool = true, tag: DependencyTagConvertible?, overrideTag: Bool, didInject: @escaping (T) -> ()) {
+    self.value = value
+    super.init(required: required, tag: tag, overrideTag: overrideTag, didInject: didInject)
+  }
+
  /**
   Creates a new wrapper for auto-injected property.
   
   - parameters:
-      - required: Defines if the property is required or not. 
-                  If container fails to inject required property it will als fail to resolve 
+      - required: Defines if the property is required or not.
+                  If container fails to inject required property it will als fail to resolve
                  the instance that defines that property. Default is `true`.
      - tag: An optional tag to use to lookup definitions when injecting this property. Default is `nil`.
-      - didInject: block that will be called when concrete instance is injected in this property. 
+      - didInject: Block that will be called when concrete instance is injected in this property.
                   Similar to `didSet` property observer. Default value does nothing.
-  */
-  public override init(required: Bool = true, tag: DependencyTagConvertible? = nil, didInject: T -> () = { _ in }) {
-    super.init(required: required, tag: tag, didInject: didInject)
+   */
+  public convenience init(required: Bool = true, didInject: @escaping (T) -> () = { _ in }) {
+    self.init(value: nil, required: required, tag: nil, overrideTag: false, didInject: didInject)
  }
  
-  public func resolve(container: DependencyContainer) throws {
-    let resolved: T? = try super.resolve(container)
+  public convenience init(required: Bool = true, tag: DependencyTagConvertible?, didInject: @escaping (T) -> () = { _ in }) {
+    self.init(value: nil, required: required, tag: tag, overrideTag: true, didInject: didInject)
+  }
+
+  public func resolve(_ container: DependencyContainer) throws {
+    let resolved: T? = try super.resolve(with: container)
    value = resolved
  }
-  
+
+  /// Returns a new wrapper with provided value.
+  public func setValue(_ value: T?) -> Injected {
+    guard (required && value != nil) || !required else {
+      fatalError("Can not set required property to nil.")
+    }
+    
+    return Injected(value: value, required: required, tag: tag, overrideTag: overrideTag, didInject: didInject)
+  }
+
 }

 /**
@@ -169,11 +200,12 @@ public final class InjectedWeak<T>: _InjectedPropertyBox<T>, AutoInjectedPropert
  //so we just rely on user reading documentation and passing AnyObject in runtime
  //also we will throw fatal error if type can not be casted to AnyObject during resolution.

+  ///The type of wrapped property.
  public static var wrappedType: Any.Type {
    return T.self
  }

-  weak var _value: AnyObject? = nil {
+  var valueBox: WeakBox<T>? = nil {
    didSet {
      if let value = value { didInject(value) }
    }
@@ -181,9 +213,14 @@ public final class InjectedWeak<T>: _InjectedPropertyBox<T>, AutoInjectedPropert
  
  ///Wrapped value.
  public var value: T? {
-    return _value as? T
+    return valueBox?.value
  }

+  init(value: T?, required: Bool = true, tag: DependencyTagConvertible?, overrideTag: Bool, didInject: @escaping (T) -> ()) {
+    self.valueBox = value.map(WeakBox.init)
+    super.init(required: required, tag: tag, overrideTag: overrideTag, didInject: didInject)
+  }
+  
  /**
   Creates a new wrapper for weak auto-injected property.
   
@@ -192,44 +229,70 @@ public final class InjectedWeak<T>: _InjectedPropertyBox<T>, AutoInjectedPropert
                  If container fails to inject required property it will als fail to resolve
                  the instance that defines that property. Default is `true`.
      - tag: An optional tag to use to lookup definitions when injecting this property. Default is `nil`.
-      - didInject: block that will be called when concrete instance is injected in this property.
+      - didInject: Block that will be called when concrete instance is injected in this property.
                   Similar to `didSet` property observer. Default value does nothing.
   */
-  public override init(required: Bool = true, tag: DependencyTagConvertible? = nil, didInject: T -> () = { _ in }) {
-    super.init(required: required, tag: tag, didInject: didInject)
+  public convenience init(required: Bool = true, didInject: @escaping (T) -> () = { _ in }) {
+    self.init(value: nil, required: required, tag: nil, overrideTag: false, didInject: didInject)
  }
  
-  public func resolve(container: DependencyContainer) throws {
-    let resolved: T? = try super.resolve(container)
-    if required && !(resolved is AnyObject) {
-      fatalError("\(T.self) can not be casted to AnyObject. InjectedWeak wrapper should be used to wrap only classes.")
+  public convenience init(required: Bool = true, tag: DependencyTagConvertible?, didInject: @escaping (T) -> () = { _ in }) {
+    self.init(value: nil, required: required, tag: tag, overrideTag: true, didInject: didInject)
+  }
+  
+  public func resolve(_ container: DependencyContainer) throws {
+    let resolved: T? = try super.resolve(with: container)
+    valueBox = resolved.map(WeakBox.init)
+  }
+
+  /// Returns a new wrapper with provided value.
+  public func setValue(_ value: T?) -> InjectedWeak {
+    guard (required && value != nil) || !required else {
+      fatalError("Can not set required property to nil.")
    }
-    _value = resolved as? AnyObject
+    
+    return InjectedWeak(value: value, required: required, tag: tag, overrideTag: overrideTag, didInject: didInject)
  }
-  
+
 }

-private class _InjectedPropertyBox<T> {
+class _InjectedPropertyBox<T> {

  let required: Bool
-  let didInject: T -> ()
+  let didInject: (T) -> ()
  let tag: DependencyContainer.Tag?
+  let overrideTag: Bool

-  init(required: Bool = true, tag: DependencyTagConvertible?, didInject: T -> () = { _ in }) {
+  init(required: Bool = true, tag: DependencyTagConvertible?, overrideTag: Bool, didInject: @escaping (T) -> () = { _ in }) {
    self.required = required
    self.tag = tag?.dependencyTag
+    self.overrideTag = overrideTag
    self.didInject = didInject
  }

-  private func resolve(container: DependencyContainer) throws -> T? {
-    let resolved: T?
-    if required {
-      resolved = try container.resolve(tag: tag) as T
+  func resolve(with container: DependencyContainer) throws -> T? {
+    let tag = overrideTag ? self.tag : container.context.tag
+    do {
+      container.context.key = container.context.key.tagged(with: tag)
+      let key = DefinitionKey(type: T.self, typeOfArguments: Void.self, tag: tag?.dependencyTag)
+      return try resolve(with: container, key: key, builder: { (factory: (Any) throws -> Any) in try factory(()) }) as? T
    }
-    else {
-      resolved = try? container.resolve(tag: tag) as T
+    catch {
+        let error = DipError.autoInjectionFailed(label: container.context.injectedInProperty, type: container.context.resolvingType, underlyingError: error)
+      if required {
+        throw error
+      }
+      else {
+        log(level: .Errors, error)
+        return nil
+      }
    }
-    return resolved
+  }
+  
+  private func resolve<U>(with container: DependencyContainer, key: DefinitionKey, builder: ((U) throws -> Any) throws -> Any) throws -> Any {
+    return try container._resolve(key: key, builder: { definition throws -> Any in
+      try builder(definition.weakFactory)
+    })
  }
  
 }
@@ -22,85 +22,65 @@
 // THE SOFTWARE.
 //

+protocol AutoWiringDefinition: DefinitionType {
+  var numberOfArguments: Int { get }
+  var autoWiringFactory: ((DependencyContainer, DependencyContainer.Tag?) throws -> Any)? { get }
+}
+
 extension DependencyContainer {
  
-  /// Tries to resolve instance using auto-wire factories
-  func _resolveByAutoWiring<T>(key: DefinitionKey) throws -> T? {
-    typealias NoArgumentsFactory = () throws -> T
-    guard key.factoryType == NoArgumentsFactory.self else { return nil }
+  /// Tries to resolve instance using auto-wiring
+  func autowire<T>(key aKey: DefinitionKey) throws -> T {
+    let key = aKey
+    guard key.typeOfArguments == Void.self else {
+      throw DipError.definitionNotFound(key: key)
+    }
    
-    let autoWiringDefinitions = self.autoWiringDefinitionsFor(T.self, tag: key.associatedTag)
-    return try _resolveEnumeratingKeys(autoWiringDefinitions, tag: key.associatedTag)
-  }
-  
-  private func autoWiringDefinitionsFor(type: Any.Type, tag: DependencyContainer.Tag?) -> [(DefinitionKey, _Definition)] {
-    var definitions = self.definitions
-      .map({ ($0.0, $0.1 as! _Definition) })
+    let autoWiringKey = try autoWiringDefinition(byKey: key).key
    
-    //filter definitions
-    definitions =  definitions
-      .filter({ $0.1.supportsAutoWiring() })
-      .filter({ $0.0.protocolType == type })
-      .filter({ $0.0.associatedTag == tag || $0.0.associatedTag == nil })
-    
-    //order definitions
-    definitions = definitions
-      .sort({ $0.1.numberOfArguments > $1.1.numberOfArguments })
-
-    definitions =
-      //first will try to use tagged definitions
-      definitions.filter({ $0.0.associatedTag == tag }) +
-      //then will use not tagged definitions
-      definitions.filter({ $0.0.associatedTag != tag })
-
-    return definitions
-  }
-  
-  /// Tries definitions one by one until one of them succeeds, otherwise returns nil
-  private func _resolveEnumeratingKeys<T>(definitions: [(DefinitionKey, _Definition)], tag: DependencyContainer.Tag?) throws -> T? {
-    for (index, definition) in definitions.enumerate() {
-      //If the next definition matches current definition then they are ambigous
-      if case definition? = definitions[next: index] {
-          throw DipError.AmbiguousDefinitions(
-            type: definition.0.protocolType,
-            definitions: [definition.1, definitions[next: index]!.1]
-        )
-      }
-      
-      if let resolved: T = _resolveKey(definition.0, tag: tag) {
-        return resolved
+    do {
+      let key = autoWiringKey.tagged(with: key.tag ?? context.tag)
+      return try _resolve(key: key) { definition in
+        try definition.autoWiringFactory!(self, key.tag) as! T
      }
    }
-    return nil
+    catch {
+      throw DipError.autoWiringFailed(type: key.type, underlyingError: error)
+    }
  }
-  
-  private func _resolveKey<T>(key: DefinitionKey, tag: DependencyContainer.Tag?) -> T? {
-    let key = DefinitionKey(protocolType: key.protocolType, factoryType: key.factoryType, associatedTag: tag)

-    return try? _resolveKey(key, builder: { definition throws -> T in
-      guard let resolved = try definition._autoWiringFactory!(self, tag) as? T else {
-        fatalError("Internal inconsistency exception! Expected type: \(T.self); Definition: \(definition)")
+  private func autoWiringDefinition(byKey key: DefinitionKey) throws -> KeyDefinitionPair {
+    do {
+      return try autoWiringDefinition(byKey: key, strictByTag: true)
+    } catch  {
+      if key.tag != nil {
+        return try autoWiringDefinition(byKey: key, strictByTag: false)
+      } else {
+        throw error
      }
-      return resolved
-    })
+    }
+  }
+  
+  private func autoWiringDefinition(byKey key: DefinitionKey, strictByTag: Bool) throws -> KeyDefinitionPair {
+    var definitions = self.definitions.map({ (key: $0.0, definition: $0.1) })
+    
+    definitions = filter(definitions: definitions, byKey: key, strictByTag: strictByTag)
+    definitions = definitions.sorted(by: { $0.definition.numberOfArguments > $1.definition.numberOfArguments })
+    
+    guard definitions.count > 0 && definitions[0].definition.numberOfArguments > 0 else {
+      throw DipError.definitionNotFound(key: key)
+    }
+    
+    let maximumNumberOfArguments = definitions.first?.definition.numberOfArguments
+    definitions = definitions.filter({ $0.definition.numberOfArguments == maximumNumberOfArguments })
+    
+    //when there are several definitions with the same number of arguments but different arguments types
+    if definitions.count > 1 && definitions[0].key.typeOfArguments != definitions[1].key.typeOfArguments {
+      let error = DipError.ambiguousDefinitions(type: key.type, definitions: definitions.map({ $0.definition }))
+      throw DipError.autoWiringFailed(type: key.type, underlyingError: error)
+    } else {
+      return definitions[0]
+    }
  }
  
 }
-
-extension CollectionType {
-  subscript(safe index: Index) -> Generator.Element? {
-    guard indices.contains(index) else { return nil }
-    return self[index]
-  }
-  subscript(next index: Index) -> Generator.Element? {
-    return self[safe: index.advancedBy(1)]
-  }
-}
-
-/// Definitions are matched if they are registered for the same tag and thier factoris accept the same number of runtime arguments.
-private func ~=(lhs: (DefinitionKey, _Definition), rhs: (DefinitionKey, _Definition)) -> Bool {
-  return
-    lhs.0.protocolType == rhs.0.protocolType &&
-      lhs.0.associatedTag == rhs.0.associatedTag &&
-      lhs.1.numberOfArguments == rhs.1.numberOfArguments
-}
@@ -0,0 +1,17 @@
+#if _runtime(_ObjC)
+  extension String {
+    func has(prefix aPrefix: String) -> Bool {
+      return hasPrefix(aPrefix)
+    }
+  }
+  
+#else
+  
+  extension String {
+    func has(prefix aPrefix: String) -> Bool {
+      return aPrefix ==
+        String(self.characters.prefix(aPrefix.characters.count))
+    }
+
+  }
+#endif
@@ -0,0 +1,120 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+///Component scope defines a strategy used by the `DependencyContainer` to manage resolved instances life cycle.
+public enum ComponentScope {
+  
+  /**
+   A new instance will be created every time it's resolved.
+   This is a default strategy. Use this strategy when you don't want instances to be shared
+   between different consumers (i.e. if it is not thread safe).
+   
+   **Example**:
+   
+   ```
+   container.register { ServiceImp() as Service }
+   container.register {
+   ServiceConsumerImp(
+   service1: try container.resolve() as Service
+   service2: try container.resolve() as Service
+   ) as ServiceConsumer
+   }
+   let consumer = container.resolve() as ServiceConsumer
+   consumer.service1 !== consumer.service2 //true
+   
+   ```
+   */
+  case unique
+  
+  /**
+   Instance resolved with the same definition will be reused until topmost `resolve(tag:)` method returns.
+   When you resolve the same object graph again the container will create new instances.
+   Use this strategy if you want different object in objects graph to share the same instance.
+   
+   - warning: Make sure this component is thread safe or accessed always from the same thread.
+   
+   **Example**:
+   
+   ```
+   container.register { ServiceImp() as Service }
+   container.register {
+   ServiceConsumerImp(
+   service1: try container.resolve() as Service
+   service2: try container.resolve() as Service
+   ) as ServiceConsumer
+   }
+   let consumer1 = container.resolve() as ServiceConsumer
+   let consumer2 = container.resolve() as ServiceConsumer
+   consumer1.service1 === consumer1.service2 //true
+   consumer2.service1 === consumer2.service2 //true
+   consumer1.service1 !== consumer2.service1 //true
+   ```
+   */
+  case shared
+  
+  /**
+   Resolved instance will be retained by the container and always reused.
+   Do not mix this life cycle with _singleton pattern_.
+   Instance will be not shared between different containers unless they collaborate.
+   
+   - warning: Make sure this component is thread safe or accessed always from the same thread.
+   
+   - note: When you override or remove definition from the container an instance
+   that was resolved with this definition will be released. When you reset
+   the container it will release all singleton instances.
+   
+   **Example**:
+   
+   ```
+   container.register(.singleton) { ServiceImp() as Service }
+   container.register {
+   ServiceConsumerImp(
+   service1: try container.resolve() as Service
+   service2: try container.resolve() as Service
+   ) as ServiceConsumer
+   }
+   let consumer1 = container.resolve() as ServiceConsumer
+   let consumer2 = container.resolve() as ServiceConsumer
+   consumer1.service1 === consumer1.service2 //true
+   consumer2.service1 === consumer2.service2 //true
+   consumer1.service1 === consumer2.service1 //true
+   ```
+   */
+  case singleton
+  
+  /**
+   The same scope as a `Singleton`, but instance will be created when container is bootstrapped.
+   
+   - seealso: `bootstrap()`
+   */
+  case eagerSingleton
+  
+  /**
+   The same scope as a `Singleton`, but container stores week reference to the resolved instance.
+   While a strong reference to the resolved instance exists resolve will return the same instance.
+   After the resolved instance is deallocated next resolve will produce a new instance.
+   */
+  case weakSingleton
+  
+}
@@ -23,226 +23,269 @@
 //

 ///A key used to store definitons in a container.
-public struct DefinitionKey : Hashable, CustomStringConvertible {
-  public let protocolType: Any.Type
-  public let factoryType: Any.Type
-  public let associatedTag: DependencyContainer.Tag?
-  
-  init(protocolType: Any.Type, factoryType: Any.Type, associatedTag: DependencyContainer.Tag? = nil) {
-    self.protocolType = protocolType
-    self.factoryType = factoryType
-    self.associatedTag = associatedTag
+public struct DefinitionKey: Hashable, CustomStringConvertible {
+  public let type: Any.Type
+  public let typeOfArguments: Any.Type
+  public private(set) var tag: DependencyContainer.Tag?
+
+  init(type: Any.Type, typeOfArguments: Any.Type, tag: DependencyContainer.Tag? = nil) {
+    self.type = type
+    self.typeOfArguments = typeOfArguments
+    self.tag = tag
  }
  
  public var hashValue: Int {
-    return "\(protocolType)-\(factoryType)-\(associatedTag)".hashValue
+    return "\(type)-\(typeOfArguments)-\(tag.desc)".hashValue
  }
  
  public var description: String {
-    return "type: \(protocolType), factory: \(factoryType), tag: \(associatedTag.desc)"
+    return "type: \(type), arguments: \(typeOfArguments), tag: \(tag.desc)"
+  }
+  
+  func tagged(with tag: DependencyContainer.Tag?) -> DefinitionKey {
+    var tagged = self
+    tagged.tag = tag
+    return tagged
+  }
+
+  /// Check two definition keys on equality by comparing their `type`, `factoryType` and `tag` properties.
+  public static func ==(lhs: DefinitionKey, rhs: DefinitionKey) -> Bool {
+    return
+      lhs.type == rhs.type &&
+      lhs.typeOfArguments == rhs.typeOfArguments &&
+      lhs.tag == rhs.tag
  }
  
 }

-/// Check two definition keys on equality by comparing their `protocolType`, `factoryType` and `associatedTag` properties.
-public func ==(lhs: DefinitionKey, rhs: DefinitionKey) -> Bool {
-  return
-    lhs.protocolType == rhs.protocolType &&
-      lhs.factoryType == rhs.factoryType &&
-      lhs.associatedTag == rhs.associatedTag
-}
-
-///Component scope defines a strategy used by the `DependencyContainer` to manage resolved instances life cycle.
-public enum ComponentScope {
-  /**
-   A new instance will be created every time it's resolved.
-   This is a default strategy. Use this strategy when you don't want instances to be shared
-   between different consumers (i.e. if it is not thread safe).
-   
-   **Example**:
-   
-   ```
-   container.register { ServiceImp() as Service }
-   container.register { 
-     ServiceConsumerImp(
-       service1: try container.resolve() as Service
-       service2: try container.resolve() as Service
-     ) as ServiceConsumer
-   }
-   let consumer = container.resolve() as ServiceConsumer
-   consumer.service1 !== consumer.service2 //true
-   
-   ```
-   */
-  case Prototype
-  
-  /**
-   Instance resolved with the same definition will be reused until topmost `resolve(tag:)` method returns.
-   When you resolve the same object graph again the container will create new instances.
-   Use this strategy if you want different object in objects graph to share the same instance.
-   
-   - warning: Make sure this component is thread safe or accessed always from the same thread.
-   
-   **Example**:
-   
-   ```
-   container.register(.ObjectGraph) { ServiceImp() as Service }
-   container.register {
-     ServiceConsumerImp(
-       service1: try container.resolve() as Service
-       service2: try container.resolve() as Service
-     ) as ServiceConsumer
-   }
-   let consumer1 = container.resolve() as ServiceConsumer
-   let consumer2 = container.resolve() as ServiceConsumer
-   consumer1.service1 === consumer1.service2 //true
-   consumer2.service1 === consumer2.service2 //true
-   consumer1.service1 !== consumer2.service1 //true
-   ```
-   */
-  case ObjectGraph
-
-  /**
-   Resolved instance will be retained by the container and always reused.
-   Do not mix this life cycle with _singleton pattern_.
-   Instance will be not shared between different containers.
-   
-   - warning: Make sure this component is thread safe or accessed always from the same thread.
-   
-   - note: When you override or remove definition from the container an instance 
-           that was resolved with this definition will be released. When you reset 
-           the container it will release all singleton instances.
-   
-   **Example**:
-   
-   ```
-   container.register(.Singleton) { ServiceImp() as Service }
-   container.register {
-     ServiceConsumerImp(
-       service1: try container.resolve() as Service
-       service2: try container.resolve() as Service
-     ) as ServiceConsumer
-   }
-   let consumer1 = container.resolve() as ServiceConsumer
-   let consumer2 = container.resolve() as ServiceConsumer
-   consumer1.service1 === consumer1.service2 //true
-   consumer2.service1 === consumer2.service2 //true
-   consumer1.service1 === consumer2.service1 //true
-   ```
-   */
-  case Singleton
-}
+///Dummy protocol to store definitions for different types in collection
+public protocol DefinitionType: class { }

 /**
- `DefinitionOf<T, F>` describes how instances of type `T` should be created when this type is resolved by the `DependencyContainer`.
+ `Definition<T, U>` describes how instances of type `T` should be created when this type is resolved by the `DependencyContainer`.
 
 - `T` is the type of the instance to resolve
- - `F` is the type of the factory that will create an instance of T.
+ - `U` is the type of runtime arguments accepted by factory that will create an instance of T.
 
- For example `DefinitionOf<Service, (String) -> Service>` is the type of definition that will create an instance of type `Service` using factory that accepts `String` argument.
+ For example `Definition<Service, String>` is the type of definition that will create an instance of type `Service` using factory that accepts `String` argument.
 */
-public final class DefinitionOf<T, F>: Definition {
+public final class Definition<T, U>: DefinitionType {
+  public typealias F = (U) throws -> T
  
+  //MARK: - _Definition
+
+  weak var container: DependencyContainer?
+  
+  let factory: F
+  let scope: ComponentScope
+  var weakFactory: ((Any) throws -> Any)!
+  var resolveProperties: ((DependencyContainer, Any) throws -> ())?
+  
+  init(scope: ComponentScope, factory: @escaping F) {
+    self.factory = factory
+    self.scope = scope
+  }
+
  /**
   Set the block that will be used to resolve dependencies of the instance.
-   This block will be called before `resolve(tag:)` returns. It can be set only once.
+   This block will be called before `resolve(tag:)` returns.
   
-   - parameter block: The block to use to resolve dependencies of the instance.
+   - parameter block: The block to resolve property dependencies of the instance.
   
   - returns: modified definition
   
   - note: To resolve circular dependencies at least one of them should use this block
-   to resolve its dependencies. Otherwise the application will enter an infinite loop and crash.
+           to resolve its dependencies. Otherwise the application will enter an infinite loop and crash.
+   
+   - note: You can call this method several times on the same definition. 
+           Container will call all provided blocks in the same order.
   
   **Example**
   
   ```swift
   container.register { ClientImp(service: try container.resolve() as Service) as Client }
-
+   
   container.register { ServiceImp() as Service }
-     .resolveDependencies { container, service in
+     .resolvingProperties { container, service in
       service.client = try container.resolve() as Client
-   }
+     }
   ```
   
   */
-  public func resolveDependencies(block: (DependencyContainer, T) throws -> ()) -> DefinitionOf<T, F> {
-    guard resolveDependenciesBlock == nil else {
-      fatalError("You can not change resolveDependencies block after it was set.")
+  @discardableResult public func resolvingProperties(_ block: @escaping (DependencyContainer, T) throws -> ()) -> Definition {
+    if let oldBlock = self.resolveProperties {
+      self.resolveProperties = {
+        try oldBlock($0, $1 as! T)
+        try block($0, $1 as! T)
+      }
+    }
+    else {
+      self.resolveProperties = { try block($0, $1 as! T) }
    }
-    self.resolveDependenciesBlock = block
    return self
  }
-  
+
  /// Calls `resolveDependencies` block if it was set.
-  func resolveDependenciesOf(resolvedInstance: Any, withContainer container: DependencyContainer) throws {
-    guard let resolvedInstance = resolvedInstance as? T else { return }
-    try self.resolveDependenciesBlock?(container, resolvedInstance)
+  func resolveProperties(of instance: Any, container: DependencyContainer) throws {
+    guard let resolvedInstance = instance as? T else { return }
+    if let forwardsTo = forwardsTo {
+      try forwardsTo.resolveProperties(of: resolvedInstance, container: container)
+    }
+    if let resolveProperties = self.resolveProperties {
+      try resolveProperties(container, resolvedInstance)
+    }
  }
  
-  let factory: F
-  private(set) var scope: ComponentScope = .Prototype
+  //MARK: - AutoWiringDefinition
  
-  private(set) var resolveDependenciesBlock: ((DependencyContainer, T) throws -> ())?
+  var autoWiringFactory: ((DependencyContainer, DependencyContainer.Tag?) throws -> Any)?
+  var numberOfArguments: Int = 0
  
-  public init(scope: ComponentScope, factory: F) {
-    self.factory = factory
-    self.scope = scope
+  //MARK: - TypeForwardingDefinition
+  
+  /// Types that can be resolved using this definition.
+  private(set) var implementingTypes: [Any.Type] = [(T?).self, (T!).self]
+  
+  /// Return `true` if type can be resolved using this definition
+  func doesImplements(type aType: Any.Type) -> Bool {
+    return implementingTypes.contains(where: { $0 == aType })
  }
  
-  private var _resolvedInstance: T?
-  
-  //Auto-wiring helpers
-  
-  private(set) var autoWiringFactory: ((DependencyContainer, DependencyContainer.Tag?) throws -> T)?
-  private(set) var numberOfArguments: Int = 0
+  //MARK: - _TypeForwardingDefinition

-  convenience init(scope: ComponentScope, factory: F, autoWiringFactory: (DependencyContainer, DependencyContainer.Tag?) throws -> T, numberOfArguments: Int) {
-    self.init(scope: scope, factory: factory)
-    self.autoWiringFactory = autoWiringFactory
-    self.numberOfArguments = numberOfArguments
+  /// Adds type as being able to be resolved using this definition
+  func _implements(type aType: Any.Type) {
+    _implements(types: [aType])
  }
-
+  
+  /// Adds types as being able to be resolved using this definition
+  func _implements(types aTypes: [Any.Type]) {
+    implementingTypes.append(contentsOf: aTypes.filter({ !doesImplements(type: $0) }))
+  }
+  
+  /// Definition to which resolution will be forwarded to
+  weak var forwardsTo: _TypeForwardingDefinition? {
+    didSet {
+      //both definitions (self and forwardsTo) can resolve
+      //each other types and each other implementing types
+      //this relationship can be used to reuse previously resolved instances
+      if let forwardsTo = forwardsTo {
+        _implements(type: forwardsTo.type)
+        _implements(types: forwardsTo.implementingTypes)
+        
+        //definitions for types that can be resolved by `forwardsTo` definition
+        //can also be used to resolve self type and it's implementing types
+        //this way container properly reuses previosly resolved instances
+        //when there are several forwarded definitions
+        //see testThatItReusesInstanceResolvedByTypeForwarding)
+        for definition in forwardsTo.forwardsFrom {
+          definition._implements(type: type)
+          definition._implements(types: implementingTypes)
+        }
+        
+        //forwardsTo can be used to resolve self type and it's implementing types
+        forwardsTo._implements(type: type)
+        forwardsTo._implements(types: implementingTypes)
+        forwardsTo.forwardsFrom.append(self)
+      }
+    }
+  }
+  
+  /// Definitions that will forward resolution to this definition
+  var forwardsFrom: [_TypeForwardingDefinition] = []
+  
 }

-///Dummy protocol to store definitions for different types in collection
-public protocol Definition: class { }
+//MARK: - _Definition

-protocol _Definition: Definition {
+protocol _Definition: AutoWiringDefinition, TypeForwardingDefinition {
+  var type: Any.Type { get }
  var scope: ComponentScope { get }
-
-  var _autoWiringFactory: ((DependencyContainer, DependencyContainer.Tag?) throws -> Any)? { get }
-  var _factory: Any { get }
-  var numberOfArguments: Int { get }
-  
-  func resolveDependenciesOf(resolvedInstance: Any, withContainer container: DependencyContainer) throws
+  var weakFactory: ((Any) throws -> Any)! { get }
+  func resolveProperties(of instance: Any, container: DependencyContainer) throws
+  var container: DependencyContainer? { get set }
 }

-extension _Definition {
-  func supportsAutoWiring() -> Bool {
-    return _autoWiringFactory != nil && numberOfArguments > 0
+//MARK: - Type Forwarding
+
+protocol _TypeForwardingDefinition: _Definition {
+  weak var forwardsTo: _TypeForwardingDefinition? { get }
+  var forwardsFrom: [_TypeForwardingDefinition] { get set }
+  func _implements(type aType: Any.Type)
+  func _implements(types aTypes: [Any.Type])
+}
+
+extension Definition: _TypeForwardingDefinition {
+  var type: Any.Type {
+    return T.self
  }
 }

-extension DefinitionOf: _Definition {
-  
-  var _resolveDependenciesBlock: ((DependencyContainer, Any) throws -> ())? {
-    return resolveDependenciesBlock.map({ block in { try block($0, $1 as! T) } })
-  }
-  
-  var _autoWiringFactory: ((DependencyContainer, DependencyContainer.Tag?) throws -> Any)? {
-    return autoWiringFactory.map({ factory in { try factory($0.0, $0.1)} })
-  }
-  
-  var _factory: Any {
-    return factory
-  }
-  
-}
-
-extension DefinitionOf: CustomStringConvertible {
+extension Definition: CustomStringConvertible {
  public var description: String {
    return "type: \(T.self), factory: \(F.self), scope: \(scope)"
  }
 }

+//MARK: - Definition Builder
+
+/// Internal class used to build definition
+class DefinitionBuilder<T, U> {
+  typealias F = (U) throws -> T
+  
+  var scope: ComponentScope!
+  var factory: F!
+  
+  var numberOfArguments: Int = 0
+  var autoWiringFactory: ((DependencyContainer, DependencyContainer.Tag?) throws -> T)?
+  
+  var forwardsTo: _Definition?
+  
+  init(configure: (DefinitionBuilder) -> ()) {
+    configure(self)
+  }
+  
+  func build() -> Definition<T, U> {
+    let factory = self.factory!
+    let definition = Definition<T, U>(scope: scope, factory: factory)
+    definition.numberOfArguments = numberOfArguments
+    definition.autoWiringFactory = autoWiringFactory
+    definition.weakFactory = { try factory($0 as! U) }
+    definition.forwardsTo = forwardsTo as? _TypeForwardingDefinition
+    return definition
+  }
+}
+
+//MARK: - KeyDefinitionPair
+
+typealias KeyDefinitionPair = (key: DefinitionKey, definition: _Definition)
+
+/// Definitions are matched if they are registered for the same tag and thier factories accept the same number of runtime arguments.
+private func ~=(lhs: KeyDefinitionPair, rhs: KeyDefinitionPair) -> Bool {
+  guard lhs.key.type == rhs.key.type else { return false }
+  guard lhs.key.tag == rhs.key.tag else { return false }
+  guard lhs.definition.numberOfArguments == rhs.definition.numberOfArguments else { return false }
+  return true
+}
+
+/// Returns key-defintion pairs with definitions able to resolve that type (directly or via type forwarding)
+/// and which tag matches provided key's tag or is nil if strictByTag is false.
+/// In the end filters defintions by type of runtime arguments.
+func filter(definitions _definitions: [KeyDefinitionPair], byKey key: DefinitionKey, strictByTag: Bool = false, byTypeOfArguments: Bool = false) -> [KeyDefinitionPair] {
+  let definitions = _definitions
+    .filter({ $0.key.type == key.type || $0.definition.doesImplements(type: key.type) })
+    .filter({ $0.key.tag == key.tag || (!strictByTag && $0.key.tag == nil) })
+  if byTypeOfArguments {
+    return definitions.filter({ $0.key.typeOfArguments == key.typeOfArguments })
+  }
+  else {
+    return definitions
+  }
+}
+
+/// Orders key-definition pairs putting first definitions registered for provided tag.
+func order(definitions _definitions: [KeyDefinitionPair], byTag tag: DependencyContainer.Tag?) -> [KeyDefinitionPair] {
+  return
+    _definitions.filter({ $0.key.tag == tag }) +
+      _definitions.filter({ $0.key.tag != tag })
+}
@@ -34,15 +34,29 @@ public final class DependencyContainer {
   
   - seealso: `DependencyTagConvertible`
   */
-  public enum Tag: Equatable {
+  public enum Tag {
    case String(StringLiteralType)
    case Int(IntegerLiteralType)
  }
  
-  var definitions = [DefinitionKey : Definition]()
-  let resolvedInstances = ResolvedInstances()
-  let lock = RecursiveLock()
+  internal(set) public var context: Context!
+  var definitions = [DefinitionKey: _Definition]()
+  var resolvedInstances = ResolvedInstances()
+  private let lock = RecursiveLock()
  
+  var bootstrapped = false
+  var bootstrapQueue: [() throws -> ()] = []
+  
+  private var _weakCollaborators: [WeakBox<DependencyContainer>] = []
+  var _collaborators: [DependencyContainer] {
+    get {
+      return _weakCollaborators.flatMap({ $0.value })
+    }
+    set {
+      _weakCollaborators = newValue.filter({ $0 !== self }).map(WeakBox.init)
+    }
+  }
+
  /**
   Designated initializer for a DependencyContainer
   
@@ -50,307 +64,266 @@ public final class DependencyContainer {
   
   - note: The `configBlock` is simply called at the end of the `init` to let you configure everything. 
           It is only present for convenience to have a cleaner syntax when declaring and initializing
-           your `DependencyContainer` instances.
+           your `DependencyContainer` instances. 
+   
+   - warning: If you use `configBlock` you need to make sure you don't create retain cycles. For example
+              there will be a retain cycle between container and its definition if you reference container
+              inside definition's factory. You can avoid that by using unowned reference to container:
+   
+   ```swift
+   let container = DependencyContainer() { container in
+     unowned let container = container
+     //register definitions
+   }
+   ```
   
   - returns: A new DependencyContainer.
   */
-  public init(@noescape configBlock: (DependencyContainer->()) = { _ in }) {
+  public init(configBlock: (DependencyContainer)->() = { _ in }) {
    configBlock(self)
  }
  
-  private func threadSafe<T>(@noescape closure: () throws -> T) rethrows -> T {
-    lock.lock()
-    defer {
-      lock.unlock()
+  /**
+   Call this method to complete container setup. After container is bootstrapped
+   you can not add or remove definitions. Trying to do so will cause runtime exception.
+   You can completely reset container, after reset you can bootstrap it again. 
+   During bootsrap container will instantiate components registered with `EagerSingleton` scope.
+   
+   - throws: `DipError` if failed to instantiate any component
+  */
+  public func bootstrap() throws {
+    try threadSafe {
+      bootstrapped = true
+      try bootstrapQueue.forEach({ try $0() })
+      bootstrapQueue.removeAll()
    }
+  }
+
+  func threadSafe<T>(_ closure: () throws -> T) rethrows -> T {
+    lock.lock()
+    defer { lock.unlock() }
    return try closure()
  }
  
 }

-// MARK: - Registering definitions
-
 extension DependencyContainer {
  
  /**
-   Register factory for type `T` and associate it with an optional tag.
-
-   - parameters:
-      - tag: The arbitrary tag to associate this factory with. Pass `nil` to associate with any tag. Default value is `nil`.
-      - scope: The scope to use for instance created by the factory.
-      - factory: The factory to register.
-
-   - returns: A registered definition.
-
-   - note: You should cast the factory return type to the protocol you want to register it for
-           (unless you want to register concrete type).
-
+   Context provides contextual information about resolution process.
+   
+   You can use the context for debugging or to pass through tag when you explicitly resolve dependencies.
+   When auto-wiring or auto-injecting tag will be implicitly passed through by the container.
+   For auto-injected properties you can disable that by providing tag (some value or `nil`) when defining property.
+   
   **Example**:
-   ```swift
-   container.register { ServiceImp() as Service }
-   container.register(tag: "service") { ServiceImp() as Service }
-   container.register(.ObjectGraph) { ServiceImp() as Service }
-   container.register { ClientImp(service: try! container.resolve() as Service) as Client }
-   ```
-   */
-  public func register<T>(tag tag: Tag? = nil, _ scope: ComponentScope = .Prototype, factory: () throws -> T) -> DefinitionOf<T, () throws -> T> {
-    let definition = DefinitionOf<T, () throws -> T>(scope: scope, factory: factory)
-    register(definition, forTag: tag)
-    return definition
-  }
-  
-  /**
-   Register generic factory associated with an optional tag.
-   
-   - parameters:
-      - tag: The arbitrary tag to associate this factory with. Pass `nil` to associate with any tag. Default value is `nil`.
-      - scope: The scope to use for instance created by the factory.
-      - factory: The factory to register.
-   
-   - returns: A registered definition.
-   
-   - note: You _should not_ call this method directly, instead call any of other `register` methods.
-   You _should_ use this method only to register dependency with more runtime arguments
-   than _Dip_ supports (currently it's up to six) like in the following example:
   
   ```swift
-   public func register<T, Arg1, Arg2, Arg3, ...>(tag: Tag? = nil, scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3, ...) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3, ...) throws -> T> {
-     return registerFactory(tag: tag, scope: scope, factory: factory)
+   class SomeServiceImp: SomeService {
+     //container will pass through the tag ("tag") used to resolve containing instance to resolve this property
+     let injected = Injected<SomeDependency>()
+   
+     //container will use "someTag" tag to resolve this property
+     let injectedTagged = Injected<SomeDependency>(tag: "someTag")
+   
+     //container will use `nil` tag to resolve this property
+     let injectedNilTag = Injected<SomeDependency>(tag: nil)
   }
+   
+   container.register {
+     //container will pass through the tag ("tag") used to resolve SomeService to resolve $0
+     SomeServiceImp(dependency: $0) as SomeService
+   }.resolvingProperties { container, service in
+     //container will use `nil` tag to resolve this dependency
+     self.dependency = try container.resolve() as SomeDependency
+   
+     //container will use current context tag ("tag") to resolve this dependency
+     self.taggedDependency = try container.resolve(tag: container.context.tag) as SomeDependency
+   }
+   
+   //container will use "tag" to resolve this instance
+   let service = try! container.resolve(tag: "tag") as SomeService
+   
   ```
-   
-   Though before you do so you should probably review your design and try to reduce number of depnedencies.
   */
-  @available(*, deprecated=4.3.0, message="Use registerFactory(tag:scope:factory:numberOfArguments:autoWiringFactory:) instead.")
-  public func registerFactory<T, F>(tag tag: DependencyTagConvertible? = nil, scope: ComponentScope, factory: F) -> DefinitionOf<T, F> {
-    let definition = DefinitionOf<T, F>(scope: scope, factory: factory)
-    register(definition, forTag: tag)
-    return definition
-  }
+  public struct Context: CustomStringConvertible, CustomDebugStringConvertible {
+    
+    internal(set) public var key: DefinitionKey
+    
+    /// Currently resolving type.
+    public var resolvingType: Any.Type {
+      return key.type
+    }

-  /**
-   Register generic factory and auto-wiring factory and associate it with an optional tag.
-   
-   - parameters:
-      - tag: The arbitrary tag to associate this factory with. Pass `nil` to associate with any tag. Default value is `nil`.
-      - scope: The scope to use for instance created by the factory.
-      - factory: The factory to register.
-      - numberOfArguments: The number of factory arguments. Will be used on auto-wiring to sort definitions.
-      - autoWiringFactory: The factory to be used on auto-wiring to resolve component.
-   
-   - returns: A registered definition.
-   
-   - note: You _should not_ call this method directly, instead call any of other `register` methods.
-   You _should_ use this method only to register dependency with more runtime arguments
-   than _Dip_ supports (currently it's up to six) like in the following example:
-   
-   ```swift
-   public func register<T, Arg1, Arg2, Arg3, ...>(tag: Tag? = nil, scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3, ...) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3, ...) throws -> T> {
-     return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: ...) { container, tag in
-        try factory(try container.resolve(tag: tag), ...)
+    /// The tag used to resolve currently resolving type.
+    public var tag: Tag? {
+      return key.tag
+    }
+    
+    /// The type that caused currently resolving type to be resolved.
+    /// `nil` for root object in a dependencies graph.
+    private(set) public var injectedInType: Any.Type?
+    
+    /// The label of the property where resolved instance will be auto-injected.
+    private(set) public var injectedInProperty: String?
+    
+    let inCollaboration: Bool
+    
+    var logErrors: Bool = true
+    
+    init(key: DefinitionKey, injectedInType: Any.Type?, injectedInProperty: String?, inCollaboration: Bool) {
+      self.key = key
+      self.injectedInType = injectedInType
+      self.injectedInProperty = injectedInProperty
+      self.inCollaboration = inCollaboration
+    }
+    
+    public var debugDescription: String {
+      return "Context(key: \(key), injectedInType: \(injectedInType.desc), injectedInProperty: \(injectedInProperty.desc) logErrors: \(logErrors))"
+    }
+    
+    public var description: String {
+      let resolvingDescription = "Resolving type \(key.type) with arguments \(key.typeOfArguments) \(key.tag != nil ? "tagged with \(key.tag!)" : "")"
+      if injectedInProperty != nil {
+        return "\(resolvingDescription) while auto-injecting property \(injectedInProperty.desc) of \(injectedInType.desc)"
+      }
+      else if injectedInType != nil {
+        return "\(resolvingDescription) while injecting in type \(injectedInType.desc)"
+      }
+      else {
+        return resolvingDescription
      }
-   }
-   ```
-   
-   Though before you do so you should probably review your design and try to reduce number of depnedencies.
-   */
-  public func registerFactory<T, F>(tag tag: DependencyTagConvertible? = nil, scope: ComponentScope, factory: F, numberOfArguments: Int, autoWiringFactory: (DependencyContainer, Tag?) throws -> T) -> DefinitionOf<T, F> {
-    let definition = DefinitionOf<T, F>(scope: scope, factory: factory, autoWiringFactory: autoWiringFactory, numberOfArguments: numberOfArguments)
-    register(definition, forTag: tag)
-    return definition
-  }
-
-  /**
-   Register definiton in the container and associate it with an optional tag.
-   Will override already registered definition for the same type and factory, associated with the same tag.
-   
-   - parameters:
-      - tag: The arbitrary tag to associate this definition with. Pass `nil` to associate with any tag. Default value is `nil`.
-      - definition: The definition to register in the container.
-   
-   */
-  public func register<T, F>(definition: DefinitionOf<T, F>, forTag tag: DependencyTagConvertible? = nil) {
-    let key = DefinitionKey(protocolType: T.self, factoryType: F.self, associatedTag: tag?.dependencyTag)
-    register(definition, forKey: key)
-  }
-  
-  func register(definition: Definition, forKey key: DefinitionKey) {
-    threadSafe {
-      definitions[key] = definition
-      resolvedInstances.singletons[key] = nil
    }
+    
  }

-}
-
-// MARK: - Resolve dependencies
-
-extension DependencyContainer {
-  
-  /**
-   Resolve a an instance of type `T`.
-   
-   If no matching definition was registered with provided `tag`,
-   container will lookup definition associated with `nil` tag.
-   
-   - parameter tag: The arbitrary tag to use to lookup definition.
-   
-   - throws: `DipError.DefinitionNotFound`, `DipError.AutoInjectionFailed`, `DipError.AmbiguousDefinitions`
-   
-   - returns: An instance of type `T`.
-   
-   - seealso: `register(tag:_:factory:)`
-   
-   **Example**:
-   ```swift
-   let service = try! container.resolve() as Service
-   let service = try! container.resolve(tag: "service") as Service
-   let service: Service = try! container.resolve()
-   ```
-   
-   */
-  public func resolve<T>(tag tag: DependencyTagConvertible? = nil) throws -> T {
-    return try resolve(tag: tag) { (factory: () throws -> T) in try factory() }
-  }
-  
-  /**
-   Resolve an instance of type `T` using generic builder closure that accepts generic factory and returns created instance.
-   
-   - parameters:
-      - tag: The arbitrary tag to use to lookup definition.
-      - builder: Generic closure that accepts generic factory and returns inctance created by that factory.
-   
-   - throws: `DipError.DefinitionNotFound`, `DipError.AutoInjectionFailed`, `DipError.AmbiguousDefinitions`
-   
-   - returns: An instance of type `T`.
-   
-   - note: You _should not_ call this method directly, instead call any of other 
-           `resolve(tag:)` or `resolve(tag:withArguments:)` methods.
-           You _should_ use this method only to resolve dependency with more runtime arguments than
-           _Dip_ supports (currently it's up to six) like in the following example:
-   
-   ```swift
-   public func resolve<T, Arg1, Arg2, Arg3, ...>(tag tag: Tag? = nil, _ arg1: Arg1, _ arg2: Arg2, _ arg3: Arg3, ...) throws -> T {
-     return try resolve(tag: tag) { (factory: (Arg1, Arg2, Arg3, ...) -> T) in factory(arg1, arg2, arg3, ...) }
-   }
-   ```
-   
-   Though before you do so you should probably review your design and try to reduce the number of dependencies.
-   */
-  public func resolve<T, F>(tag tag: DependencyTagConvertible? = nil, builder: F throws -> T) throws -> T {
-    let key = DefinitionKey(protocolType: T.self, factoryType: F.self, associatedTag: tag?.dependencyTag)
-
-    do {
-      //first we try to find defintion that exactly matches parameters
-      return try _resolveKey(key, builder: { definition throws -> T in
-        guard let factory = definition._factory as? F else {
-          throw DipError.DefinitionNotFound(key: key)
-        }
-        return try builder(factory)
-      })
-    }
-    catch {
-      switch error {
-      case let DipError.DefinitionNotFound(errorKey) where key == errorKey:
-        //then if no definition found we try atuo-wiring
-        return try threadSafe {
-          guard let resolved: T = try _resolveByAutoWiring(key) else {
-            throw error
+  /// Pushes new context created with provided values and calls block. When block returns previous context is restored.
+  /// When popped to initial (root) context will release all references to resolved instances and call `Resolvable` callbacks.
+  func inContext<T>(key aKey: DefinitionKey, injectedInType: Any.Type?, injectedInProperty: String? = nil, inCollaboration: Bool = false, container: DependencyContainer? = nil, logErrors: Bool! = nil, block: () throws -> T) rethrows -> T {
+    let key = aKey
+    return try threadSafe {
+      let currentContext = self.context
+      
+      defer {
+        context = currentContext
+        
+        //clean instances pool if it is owned not by other container
+        if context == nil {
+          resolvedInstances.resolvedInstances.removeAll()
+          for (key, instance) in resolvedInstances.sharedWeakSingletons {
+            if resolvedInstances.sharedWeakSingletons[key] is WeakBoxType { continue }
+            resolvedInstances.sharedWeakSingletons[key] = WeakBox(instance)
          }
-          return resolved
+          for (key, instance) in resolvedInstances.weakSingletons {
+            if resolvedInstances.weakSingletons[key] is WeakBoxType { continue }
+            resolvedInstances.weakSingletons[key] = WeakBox(instance)
+          }
+          
+          for resolvedInstance in resolvedInstances.resolvableInstances.reversed() {
+            resolvedInstance.didResolveDependencies()
+          }
+          resolvedInstances.resolvableInstances.removeAll()
        }
-      default:
+      }
+      
+      context = Context(
+        key: key,
+        injectedInType: injectedInType,
+        injectedInProperty: injectedInProperty,
+        inCollaboration: inCollaboration
+      )
+      context.logErrors = logErrors ?? currentContext?.logErrors ?? true
+      
+      do {
+        return try block()
+      }
+      catch {
+        if context.logErrors { log(level: .Errors, error) }
        throw error
      }
    }
  }

-  /// Lookup definition by the key and use it to resolve instance. Fallback to the key with `nil` tag.
-  func _resolveKey<T>(key: DefinitionKey, builder: _Definition throws -> T) throws -> T {
-    return try threadSafe {
-      let nilTagKey = key.associatedTag.map { _ in DefinitionKey(protocolType: T.self, factoryType: key.factoryType, associatedTag: nil) }
+}

-      guard let definition = (self.definitions[key] ?? self.definitions[nilTagKey]) as? _Definition else {
-        throw DipError.DefinitionNotFound(key: key)
-      }
-      return try self._resolveDefinition(definition, usingKey: key, builder: builder)
+//MARK: - Collaborating containers
+
+extension DependencyContainer {
+  
+  /**
+   Adds collaborating containers as weak references. Circular references are allowed.
+   References to the container itself are ignored.
+   */
+  public func collaborate(with containers: DependencyContainer...) {
+    collaborate(with: containers)
+  }
+  
+  /**
+   Adds collaborating containers as weak references. Circular references are allowed.
+   References to the container itself are ignored.
+   */
+  public func collaborate(with containers: [DependencyContainer]) {
+    _collaborators += containers
+    for container in containers {
+      container._collaborators += [self]
+      container.resolvedInstances.sharedSingletonsBox = self.resolvedInstances.sharedSingletonsBox
+      container.resolvedInstances.sharedWeakSingletonsBox = self.resolvedInstances.sharedWeakSingletonsBox
+      updateCollaborationReferences(between: container, and: self)
    }
  }
  
-  /// Actually resolve dependency.
-  private func _resolveDefinition<T>(definition: _Definition, usingKey key: DefinitionKey, builder: _Definition throws -> T) rethrows -> T {
-    return try resolvedInstances.resolve {
-      if let previouslyResolved: T = resolvedInstances.previouslyResolvedInstance(forKey: key, inScope: definition.scope) {
-        return previouslyResolved
-      }
-      else {
-        let resolvedInstance = try builder(definition)
-        
-        //when builder calls factory it will in turn resolve sub-dependencies (if there are any)
-        //when it returns instance that we try to resolve here can be already resolved
-        //so we return it, throwing away instance created by previous call to builder
-        if let previouslyResolved: T = resolvedInstances.previouslyResolvedInstance(forKey: key, inScope: definition.scope) {
-          return previouslyResolved
-        }
-        
-        resolvedInstances.storeResolvedInstance(resolvedInstance, forKey: key, inScope: definition.scope)
-        
-        try definition.resolveDependenciesOf(resolvedInstance, withContainer: self)
-        try autoInjectProperties(resolvedInstance)
-        
-        return resolvedInstance
-      }
+  private func updateCollaborationReferences(between container: DependencyContainer, and collaborator: DependencyContainer) {
+    for container in container._collaborators {
+      guard container.resolvedInstances.sharedSingletonsBox !== collaborator.resolvedInstances.sharedSingletonsBox else { continue }
+      container.resolvedInstances.sharedSingletonsBox = collaborator.resolvedInstances.sharedSingletonsBox
+      container.resolvedInstances.sharedWeakSingletonsBox = collaborator.resolvedInstances.sharedWeakSingletonsBox
+      updateCollaborationReferences(between: container, and: collaborator)
    }
  }
  
-  ///Pool to hold instances, created during call to `resolve()`.
-  ///Before `resolve()` returns pool is drained.
-  class ResolvedInstances {
-    var resolvedInstances = [DefinitionKey: Any]()
-    var singletons = [DefinitionKey: Any]()
-    var resolvableInstances = [Resolvable]()
-
-    func storeResolvedInstance<T>(instance: T, forKey key: DefinitionKey, inScope scope: ComponentScope) {
-      switch scope {
-      case .Singleton: singletons[key] = instance
-      case .ObjectGraph: resolvedInstances[key] = instance
-      case .Prototype: break
-      }
+  /// Tries to resolve key using collaborating containers
+  func collaboratingResolve<T>(key aKey: DefinitionKey, builder: (_Definition) throws -> T) -> T? {
+    let key = aKey
+    for collaborator in _collaborators {
+      //if container is already in a context resolving this type
+      //it means that it has been already called to resolve this type,
+      //so there is probably a cercular reference between containers.
+      //To break it skip this container
+      if let context = collaborator.context, context.resolvingType == key.type && context.tag == key.tag { continue }
      
-      if let resolvable = instance as? Resolvable {
-        resolvableInstances.append(resolvable)
-      }
-    }
-    
-    func previouslyResolvedInstance<T>(forKey key: DefinitionKey, inScope scope: ComponentScope) -> T? {
-      switch scope {
-      case .Singleton: return singletons[key] as? T
-      case .ObjectGraph: return resolvedInstances[key] as? T
-      case .Prototype: return nil
-      }
-    }
-    
-    private var depth: Int = 0
-    
-    func resolve<T>(@noescape block: () throws ->T) rethrows -> T {
-      depth = depth + 1
-      
-      defer {
-        depth = depth - 1
-        if depth == 0 {
-          // We call didResolveDependencies only at this point
-          // because this is a point when dependencies graph is complete.
-          for resolvedInstance in resolvableInstances {
-            resolvedInstance.didResolveDependencies()
+      do {
+        //Pass current container's instances pool to collect instances resolved by collaborator
+        let resolvedInstances = collaborator.resolvedInstances
+        collaborator.resolvedInstances = self.resolvedInstances
+        //Set collaborator context to preserve current container context
+        let context = collaborator.context
+        collaborator.context = self.context
+        defer {
+          collaborator.context = context
+          collaborator.resolvedInstances = resolvedInstances
+          
+          for (key, resolvedSingleton) in self.resolvedInstances.singletons {
+            collaborator.resolvedInstances.singletons[aKey] = resolvedSingleton
+          }
+          for (_, resolvedSingleton) in self.resolvedInstances.weakSingletons {
+            guard collaborator.definition(matching: aKey) != nil else { continue }
+            collaborator.resolvedInstances.weakSingletons[aKey] = WeakBox(resolvedSingleton)
+          }
+          for (_, resolved) in self.resolvedInstances.resolvedInstances {
+            guard collaborator.definition(matching: aKey) != nil else { continue }
+            collaborator.resolvedInstances.resolvedInstances[aKey] = resolved
          }
-          resolvedInstances.removeAll()
-          resolvableInstances.removeAll()
        }
+        
+        let resolved = try collaborator.inContext(key:key, injectedInType: self.context.injectedInType, injectedInProperty: self.context.injectedInProperty, inCollaboration: true, logErrors: false) {
+          try collaborator._resolve(key: key, builder: builder)
+        }
+
+        return resolved
      }
-      
-      let resolved = try block()
-      return resolved
+      catch { }
    }
+    return nil
  }
  
 }
@@ -361,20 +334,30 @@ extension DependencyContainer {
  
  /**
   Removes definition registered in the container.
-
+   
   - parameters:
      - tag: The tag used to register definition.
      - definition: The definition to remove
   */
-  public func remove<T, F>(definition: DefinitionOf<T, F>, forTag tag: DependencyTagConvertible? = nil) {
-    let key = DefinitionKey(protocolType: T.self, factoryType: F.self, associatedTag: tag?.dependencyTag)
-    remove(definitionForKey: key)
+  public func remove<T, U>(_ definition: Definition<T, U>, tag: DependencyTagConvertible? = nil) {
+    _remove(definition: definition, tag: tag)
  }
  
-  func remove(definitionForKey key: DefinitionKey) {
+  func _remove<T, U>(definition aDefinition: Definition<T, U>, tag: DependencyTagConvertible? = nil) {
+    let key = DefinitionKey(type: T.self, typeOfArguments: U.self, tag: tag?.dependencyTag)
+    _remove(definitionForKey: key)
+  }
+  
+  func _remove(definitionForKey key: DefinitionKey) {
+    precondition(!bootstrapped, "You can not modify container's definitions after it was bootstrapped.")
+    
    threadSafe {
+      definitions[key]?.container = nil
      definitions[key] = nil
      resolvedInstances.singletons[key] = nil
+      resolvedInstances.weakSingletons[key] = nil
+      resolvedInstances.sharedSingletons[key] = nil
+      resolvedInstances.sharedWeakSingletons[key] = nil
    }
  }

@@ -383,32 +366,82 @@ extension DependencyContainer {
   */
  public func reset() {
    threadSafe {
+      definitions.forEach { $0.1.container = nil }
      definitions.removeAll()
      resolvedInstances.singletons.removeAll()
+      resolvedInstances.weakSingletons.removeAll()
+      resolvedInstances.sharedSingletons.removeAll()
+      resolvedInstances.sharedWeakSingletons.removeAll()
+      bootstrapped = false
    }
  }

 }

+// MARK: - Validation
+
+extension DependencyContainer {
+  
+  /**
+   Validates container configuration trying to resolve each registered definition one by one.
+   If definition fails to be resolved without arguments will search provided arguments array
+   for arguments matched by type and try to resolve this definition using these arguments.
+   If there are no matching arguments will rethrow original error.
+   
+   - parameter arguments: set of arguments to use to resolve registered definitions.
+                          Use a tuple for registered factories that accept several runtime arguments.
+   */
+  public func validate(_ arguments: Any...) throws {
+    try _validate(arguments: arguments)
+  }
+  
+  func _validate(arguments _arguments: [Any]) throws {
+    let arguments = _arguments
+    validateNextDefinition: for (key, _) in definitions {
+      do {
+        //try to resolve key using provided arguments
+        for argumentsSet in arguments {
+          guard type(of: argumentsSet) == key.typeOfArguments else { continue }
+          do {
+            let _ = try inContext(key:key, injectedInType: nil) {
+              try self._resolve(key: key, builder: { definition throws -> Any in
+                try definition.weakFactory(argumentsSet)
+              })
+            }
+            continue validateNextDefinition
+          }
+          catch let error as DipError {
+            throw error
+          }
+            //ignore other errors
+          catch { log(level: .Errors, error) }
+        }
+        
+        //try to resolve key using auto-wiring
+        do {
+          let _ = try self.resolve(key.type, tag: key.tag)
+        }
+        catch let error as DipError {
+          throw error
+        }
+          //ignore other errors
+        catch { log(level: .Errors, error) }
+      }
+    }
+  }
+}
+
 extension DependencyContainer: CustomStringConvertible {
  
  public var description: String {
-    return "Definitions: \(definitions.count)\n" + definitions.map({ "\($0.0)" }).joinWithSeparator("\n")
+    return "Definitions: \(definitions.count)\n" + definitions.map({ "\($0.0)" }).joined(separator: "\n")
  }
  
 }

-//MARK: - Resolvable
-
-/// Conform to this protocol when you need to have a callback when all the dependencies are injected.
-public protocol Resolvable {
-  /// This method is called by the container when all dependencies of the instance are resolved.
-  func didResolveDependencies()
-}
-
 //MARK: - DependencyTagConvertible

-/// Implement this protocol of your type if you want to use its instances as `DependencyContainer`'s tags.
+/// Implement this protocol on your type if you want to use its instances as `DependencyContainer`'s tags.
 /// `DependencyContainer.Tag`, `String`, `Int` and any `RawRepresentable` with `RawType` of `String` or `Int` by default confrom to this protocol.
 public protocol DependencyTagConvertible {
  var dependencyTag: DependencyContainer.Tag { get }
@@ -444,7 +477,7 @@ extension DependencyTagConvertible where Self: RawRepresentable, Self.RawValue =
  }
 }

-extension DependencyContainer.Tag: StringLiteralConvertible {
+extension DependencyContainer.Tag: ExpressibleByStringLiteral {
  
  public init(stringLiteral value: StringLiteralType) {
    self = .String(value)
@@ -460,7 +493,7 @@ extension DependencyContainer.Tag: StringLiteralConvertible {
  
 }

-extension DependencyContainer.Tag: IntegerLiteralConvertible {
+extension DependencyContainer.Tag: ExpressibleByIntegerLiteral {
  
  public init(integerLiteral value: IntegerLiteralType) {
    self = .Int(value)
@@ -468,61 +501,17 @@ extension DependencyContainer.Tag: IntegerLiteralConvertible {
  
 }

-public func ==(lhs: DependencyContainer.Tag, rhs: DependencyContainer.Tag) -> Bool {
-  switch (lhs, rhs) {
-  case let (.String(lhsString), .String(rhsString)):
-    return lhsString == rhsString
-  case let (.Int(lhsInt), .Int(rhsInt)):
-    return lhsInt == rhsInt
-  default:
-    return false
-  }
-}
+extension DependencyContainer.Tag: Equatable {

-//MARK: - DipError
-
-/**
- Errors thrown by `DependencyContainer`'s methods.
- 
- - seealso: `resolve(tag:)`
-*/
-public enum DipError: ErrorType, CustomStringConvertible {
-  
-  /**
-   Thrown by `resolve(tag:)` if no matching definition was registered in container.
-   
-   - parameter key: definition key used to lookup matching definition
-  */
-  case DefinitionNotFound(key: DefinitionKey)
-
-  /**
-   Thrown by `resolve(tag:)` if failed to auto-inject required property.
-   
-   - parameters:
-      - label: The name of the property
-      - type: The type of the property
-      - underlyingError: The error that caused auto-injection to fail
-  */
-  case AutoInjectionFailed(label: String?, type: Any.Type, underlyingError: ErrorType)
-
-  /**
-   Thrown by `resolve(tag:)` if found ambigous definitions registered for resolved type
-   
-   - parameters:
-      - type: The type that failed to be resolved
-      - definitions: Ambiguous definitions
-  */
-  case AmbiguousDefinitions(type: Any.Type, definitions: [Definition])
-  
-  public var description: String {
-    switch self {
-    case let .DefinitionNotFound(key):
-      return "No definition registered for \(key).\nCheck the tag, type you try to resolve, number, order and types of runtime arguments passed to `resolve()` and match them with registered factories for type \(key.protocolType)."
-    case let .AutoInjectionFailed(label, type, error):
-      return "Failed to auto-inject property \"\(label.desc)\" of type \(type). \(error)"
-    case let .AmbiguousDefinitions(type, definitions):
-      return "Ambiguous definitions for \(type):\n" +
-      definitions.map({ "\($0)" }).joinWithSeparator(";\n")
+  public static func ==(lhs: DependencyContainer.Tag, rhs: DependencyContainer.Tag) -> Bool {
+    switch (lhs, rhs) {
+    case let (.String(lhsString), .String(rhsString)):
+      return lhsString == rhsString
+    case let (.Int(lhsInt), .Int(rhsInt)):
+      return lhsInt == rhsInt
+    default:
+      return false
    }
  }
+
 }
@@ -0,0 +1,94 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+/**
+ Errors thrown by `DependencyContainer`'s methods.
+ 
+ - seealso: `resolve(tag:)`
+ */
+public enum DipError: Error, CustomStringConvertible {
+  
+  /**
+   Thrown by `resolve(tag:)` if no matching definition was registered in container.
+   
+   - parameter key: definition key used to lookup matching definition
+   */
+  case definitionNotFound(key: DefinitionKey)
+  
+  /**
+   Thrown by `resolve(tag:)` if failed to auto-inject required property.
+   
+   - parameters:
+      - label: The name of the property
+      - type: The type of the property
+      - underlyingError: The error that caused auto-injection to fail
+   */
+  case autoInjectionFailed(label: String?, type: Any.Type, underlyingError: Error)
+  
+  /**
+   Thrown by `resolve(tag:)` if failed to auto-wire a type.
+   
+   - parameters:
+      - type: The type that failed to be resolved by auto-wiring
+      - underlyingError: The error that cause auto-wiring to fail
+   */
+  case autoWiringFailed(type: Any.Type, underlyingError: Error)
+  
+  /**
+   Thrown when auto-wiring type if several definitions with the same number of runtime arguments
+   are registered for that type.
+   
+   - parameters:
+      - type: The type that failed to be resolved by auto-wiring
+      - definitions: Ambiguous definitions
+   */
+  case ambiguousDefinitions(type: Any.Type, definitions: [DefinitionType])
+  
+  /**
+   Thrown by `resolve(tag:)` if resolved instance does not implemenet resolved type (i.e. when type-forwarding).
+   
+   - parameters:
+      - resolved: Resolved instance
+      - key: Definition key used to resolve instance
+   */
+  case invalidType(resolved: Any?, key: DefinitionKey)
+  
+  public var description: String {
+    switch self {
+    case let .definitionNotFound(key):
+      return "No definition registered for \(key).\nCheck the tag, type you try to resolve, number, order and types of runtime arguments passed to `resolve()` and match them with registered factories for type \(key.type)."
+    case let .autoInjectionFailed(label, type, error):
+      return "Failed to auto-inject property \"\(label.desc)\" of type \(type). \(error)"
+    case let .autoWiringFailed(type, error):
+      return "Failed to auto-wire type \"\(type)\". \(error)"
+    case let .ambiguousDefinitions(type, definitions):
+      return "Ambiguous definitions for \(type):\n" +
+        definitions.map({ "\($0)" }).joined(separator: ";\n")
+    case let .invalidType(resolved, key):
+      return "Resolved instance \(resolved ?? "nil") does not implement expected type \(key.type)."
+    }
+  }
+  
+}
+
@@ -0,0 +1,84 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+extension DependencyContainer {
+  /**
+   Registers definition for passed type.
+   
+   If instance created by factory of definition, passed as a first parameter,
+   does not implement type passed in a `type` parameter,
+   container will throw `DipError.DefinitionNotFound` error when trying to resolve that type.
+   
+   - parameters:
+      - definition: Definition to register
+      - type: Type to register definition for
+      - tag: Optional tag to associate definition with. Default is `nil`.
+   
+   - returns: New definition registered for passed type.
+   */
+  @discardableResult public func register<T, U, F>(_ definition: Definition<T, U>, type: F.Type, tag: DependencyTagConvertible? = nil) -> Definition<F, U> {
+    return _register(definition: definition, type: type, tag: tag)
+  }
+
+  /**
+   Register definiton in the container and associate it with an optional tag.
+   Will override already registered definition for the same type and factory, associated with the same tag.
+   
+   - parameters:
+      - tag: The arbitrary tag to associate this definition with. Pass `nil` to associate with any tag. Default value is `nil`.
+      - definition: The definition to register in the container.
+   
+   */
+  public func register<T, U>(_ definition: Definition<T, U>, tag: DependencyTagConvertible? = nil) {
+    _register(definition: definition, tag: tag)
+  }
+
+}
+
+extension DependencyContainer {
+  
+  func _register<T, U>(definition aDefinition: Definition<T, U>, tag: DependencyTagConvertible? = nil) {
+    precondition(!bootstrapped, "You can not modify container's definitions after it was bootstrapped.")
+    let definition = aDefinition
+    threadSafe {
+      let key = DefinitionKey(type: T.self, typeOfArguments: U.self, tag: tag?.dependencyTag)
+      if let _ = definitions[key] {
+        _remove(definitionForKey: key)
+      }
+      
+      definition.container = self
+      definitions[key] = definition
+      resolvedInstances.singletons[key] = nil
+      resolvedInstances.weakSingletons[key] = nil
+      resolvedInstances.sharedSingletons[key] = nil
+      resolvedInstances.sharedWeakSingletons[key] = nil
+      
+      if .eagerSingleton == definition.scope {
+        bootstrapQueue.append({ _ = try self.resolve(tag: tag) as T })
+      }
+    }
+  }
+  
+}
+
@@ -0,0 +1,330 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+extension DependencyContainer {
+  
+  /**
+   Resolve an instance of type `T`.
+   
+   If no matching definition was registered with provided `tag`,
+   container will lookup definition associated with `nil` tag.
+   
+   - parameter tag: The arbitrary tag to use to lookup definition.
+   
+   - throws: `DipError.DefinitionNotFound`, `DipError.AutoInjectionFailed`, `DipError.AmbiguousDefinitions`, `DipError.InvalidType`
+   
+   - returns: An instance of type `T`.
+   
+   **Example**:
+   ```swift
+   let service = try! container.resolve() as Service
+   let service = try! container.resolve(tag: "service") as Service
+   let service: Service = try! container.resolve()
+   ```
+   
+   - seealso: `register(_:type:tag:factory:)`
+   */
+  public func resolve<T>(tag: DependencyTagConvertible? = nil) throws -> T {
+    return try _resolve(tag: tag) { (factory: () throws -> T) in try factory() }
+  }
+
+  /**
+   Resolve an instance of requested type. Weakly-typed alternative of `resolve(tag:)`
+   
+   - warning: This method does not make any type checks, so there is no guaranty that
+              resulting instance is actually an instance of requested type.
+              That can happen if you register forwarded type that is not implemented by resolved instance.
+   
+   - parameters:
+      - type: Type to resolve
+      - tag: The arbitrary tag to use to lookup definition.
+   
+   - throws: `DipError.DefinitionNotFound`, `DipError.AutoInjectionFailed`, `DipError.AmbiguousDefinitions`, `DipError.InvalidType`
+   
+   - returns: An instance of requested type.
+
+   **Example**:
+   ```swift
+   let service = try! container.resolve(Service.self) as! Service
+   let service = try! container.resolve(Service.self, tag: "service") as! Service
+   ```
+
+   - seealso: `resolve(tag:)`, `register(_:type:tag:factory:)`
+   */
+  public func resolve(_ type: Any.Type, tag: DependencyTagConvertible? = nil) throws -> Any {
+    return try resolve(type, tag: tag) { (factory: () throws -> Any) in try factory() }
+  }
+  
+  /**
+   Resolve an instance of type `T` using generic builder closure that accepts generic factory and returns created instance.
+   
+   - parameters:
+      - tag: The arbitrary tag to use to lookup definition.
+      - builder: Generic closure that accepts generic factory and returns inctance created by that factory.
+   
+   - throws: `DipError.DefinitionNotFound`, `DipError.AutoInjectionFailed`, `DipError.AmbiguousDefinitions`, `DipError.InvalidType`
+   
+   - returns: An instance of type `T`.
+   
+   - note: You _should not_ call this method directly, instead call any of other 
+           `resolve(tag:)` or `resolve(tag:withArguments:)` methods.
+           You _should_ use this method only to resolve dependency with more runtime arguments than
+           _Dip_ supports (currently it's up to six) like in the following example:
+   
+   ```swift
+   public func resolve<T, A, B, C, ...>(tag: Tag? = nil, _ arg1: A, _ arg2: B, _ arg3: C, ...) throws -> T {
+     return try resolve(tag: tag) { factory in factory(arg1, arg2, arg3, ...) }
+   }
+   ```
+   
+   Though before you do so you should probably review your design and try to reduce the number of dependencies.
+   */
+  public func resolve<T, U>(tag: DependencyTagConvertible? = nil, builder: ((U) throws -> T) throws -> T) throws -> T {
+    return try _resolve(tag: tag, builder: builder)
+  }
+
+  public func resolve<T>(tag: DependencyTagConvertible? = nil, builder: (() throws -> T) throws -> T) throws -> T {
+    return try _resolve(tag: tag, builder: builder)
+  }
+
+  /**
+   Resolve an instance of provided type using builder closure. Weakly-typed alternative of `resolve(tag:builder:)`
+   
+   - seealso: `resolve(tag:builder:)`
+  */
+  public func resolve<U>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, builder: ((U) throws -> Any) throws -> Any) throws -> Any {
+    return try _resolve(type: type, tag: tag, builder: builder)
+  }
+
+  public func resolve(_ type: Any.Type, tag: DependencyTagConvertible? = nil, builder: (() throws -> Any) throws -> Any) throws -> Any {
+    return try _resolve(type: type, tag: tag, builder: builder)
+  }
+
+}
+
+extension DependencyContainer {
+  
+  func _resolve<T>(tag aTag: DependencyTagConvertible? = nil, builder: (() throws -> T) throws -> T) throws -> T {
+    return try resolve(T.self, tag: aTag, builder: { factory in
+      try withoutActuallyEscaping(factory, do: { (factory) throws -> T in
+        try builder({ try factory() as! T })
+      })
+    }) as! T
+  }
+  
+  func _resolve(type aType: Any.Type, tag: DependencyTagConvertible? = nil, builder: (() throws -> Any) throws -> Any) throws -> Any {
+    let key = DefinitionKey(type: aType, typeOfArguments: Void.self, tag: tag?.dependencyTag)
+    
+    return try inContext(key:key, injectedInType: context?.resolvingType) {
+      try self._resolve(key: key, builder: { definition in
+        try builder { try definition.weakFactory(()) }
+      })
+    }
+  }
+  
+  func _resolve<T, U>(tag aTag: DependencyTagConvertible? = nil, builder: ((U) throws -> T) throws -> T) throws -> T {
+    return try resolve(T.self, tag: aTag, builder: { factory in
+      try withoutActuallyEscaping(factory, do: { (factory) throws -> T in
+        try builder({ try factory($0) as! T })
+      })
+    }) as! T
+  }
+  
+  func _resolve<U>(type aType: Any.Type, tag: DependencyTagConvertible? = nil, builder: ((U) throws -> Any) throws -> Any) throws -> Any {
+    let key = DefinitionKey(type: aType, typeOfArguments: U.self, tag: tag?.dependencyTag)
+    
+    return try inContext(key:key, injectedInType: context?.resolvingType) {
+      try self._resolve(key: key, builder: { definition in
+        try builder(definition.weakFactory)
+      })
+    }
+  }
+  
+  /// Lookup definition by the key and use it to resolve instance. Fallback to the key with `nil` tag.
+  func _resolve<T>(key aKey: DefinitionKey, builder: (_Definition) throws -> T) throws -> T {
+    guard let matching = self.definition(matching: aKey) else {
+      do {
+        return try autowire(key: aKey)
+      } catch {
+        if let resolved = collaboratingResolve(key: aKey, builder: builder) {
+          return resolved
+        } else {
+          throw error
+        }
+      }
+    }
+    
+    let (key, definition) = matching
+    
+    //first search for already resolved instance for this type or any of forwarding types
+    if let previouslyResolved: T = previouslyResolved(for: definition, key: key) {
+      log(level: .Verbose, "Reusing previously resolved instance \(previouslyResolved)")
+      return previouslyResolved
+    }
+    
+    log(level: .Verbose, context)
+    var resolvedInstance = try builder(definition)
+    
+    /*
+     Strongly-typed `resolve(tag:builder:)` calls weakly-typed `resolve(_:tag:builder:)`,
+     so `T` will be `Any` at runtime, erasing type information when this method returns.
+     When we try to cast result of `Any` to generic type T Swift fails to cast it.
+     The same happens in the following code snippet:
+     
+     let optService: Service? = ServiceImp()
+     let anyService: Any = optService
+     let service: Service = anyService as! Service
+     
+     That happens because when Optional is casted to Any Swift can not implicitly unwrap it with as operator.
+     As a workaround we detect boxing here and unwrap it so that we return not a box, but wrapped instance.
+     */
+    if let box = resolvedInstance as? BoxType, let unboxed = box.unboxed as? T {
+      resolvedInstance = unboxed
+    }
+    
+    //when builder calls factory it will in turn resolve sub-dependencies (if there are any)
+    //when it returns instance that we try to resolve here can be already resolved
+    //so we return it, throwing away instance created by previous call to builder
+    if let previouslyResolved: T = previouslyResolved(for: definition, key: key) {
+      log(level: .Verbose, "Reusing previously resolved instance \(previouslyResolved)")
+      return previouslyResolved
+    }
+    
+    resolvedInstances[key: key, inScope: definition.scope, context: context] = resolvedInstance
+    
+    if let resolvable = resolvedInstance as? Resolvable {
+      resolvedInstances.resolvableInstances.append(resolvable)
+      resolvable.resolveDependencies(self)
+    }
+    
+    try autoInjectProperties(in: resolvedInstance)
+    try definition.resolveProperties(of: resolvedInstance, container: self)
+    
+    log(level: .Verbose, "Resolved type \(key.type) with \(resolvedInstance)")
+    return resolvedInstance
+  }
+  
+  private func previouslyResolved<T>(for definition: _Definition, key: DefinitionKey) -> T? {
+    //first check if exact key was already resolved
+    if let previouslyResolved = resolvedInstances[key: key, inScope: definition.scope, context: context] as? T {
+      return previouslyResolved
+    }
+    //then check if any related type was already resolved
+    let keys = definition.implementingTypes.map({
+      DefinitionKey(type: $0, typeOfArguments: key.typeOfArguments, tag: key.tag)
+    })
+    for key in keys {
+      if let previouslyResolved = resolvedInstances[key: key, inScope: definition.scope, context: context] as? T {
+        return previouslyResolved
+      }
+    }
+    return nil
+  }
+  
+  /// Searches for definition that matches provided key
+  func definition(matching key: DefinitionKey) -> KeyDefinitionPair? {
+    if let definition = (self.definitions[key] ?? self.definitions[key.tagged(with: nil)]) {
+      return (key, definition)
+    }
+    
+    //if no definition registered for exact type try to find type-forwarding definition that can resolve the type
+    //that will actually happen only when resolving optionals
+    if definitions.filter({ $0.0.type == key.type }).isEmpty {
+      return typeForwardingDefinition(forKey: key)
+    }
+    return nil
+  }
+  
+}
+
+///Pool to hold instances, created during call to `resolve()`.
+///Before `resolve()` returns pool is drained.
+class ResolvedInstances {
+  
+  var resolvedInstances = [DefinitionKey: Any]()
+  var resolvableInstances = [Resolvable]()
+  
+  //singletons are stored using reference type wrapper to be able to share them between containers
+  var sharedSingletonsBox = Box<[DefinitionKey: Any]>([:])
+  var sharedSingletons: [DefinitionKey: Any] {
+    get { return sharedSingletonsBox.unboxed }
+    set { sharedSingletonsBox.unboxed = newValue }
+  }
+  var singletons = [DefinitionKey: Any]()
+  
+  var sharedWeakSingletonsBox = Box<[DefinitionKey: Any]>([:])
+  var sharedWeakSingletons: [DefinitionKey: Any] {
+    get { return sharedWeakSingletonsBox.unboxed }
+    set { sharedWeakSingletonsBox.unboxed = newValue }
+  }
+  var weakSingletons = [DefinitionKey: Any]()
+  
+  subscript(key key: DefinitionKey, inScope scope: ComponentScope, context context: DependencyContainer.Context) -> Any? {
+    get {
+      switch scope {
+      case .singleton, .eagerSingleton:
+        return context.inCollaboration ? sharedSingletons[key] : singletons[key]
+      case .weakSingleton:
+        let singletons = context.inCollaboration ? sharedWeakSingletons : weakSingletons
+        if let boxed = singletons[key] as? WeakBoxType { return boxed.unboxed }
+        else { return singletons[key] }
+      case .shared:
+        return resolvedInstances[key]
+      case .unique:
+        return nil
+      }
+    }
+    set {
+      switch scope {
+      case .singleton, .eagerSingleton:
+        sharedSingletons[key] = newValue
+        singletons[key] = newValue
+      case .weakSingleton:
+        sharedWeakSingletons[key] = newValue
+        weakSingletons[key] = newValue
+      case .shared:
+        resolvedInstances[key] = newValue
+      case .unique:
+        break
+      }
+    }
+  }
+  
+}
+
+//MARK: - Resolvable
+
+/// Resolvable protocol provides some extension points for resolving dependencies with property injection.
+public protocol Resolvable {
+  /// This method will be called right after instance is created by the container.
+  func resolveDependencies(_ container: DependencyContainer)
+  /// This method will be called when all dependencies of the instance are resolved.
+  /// When resolving objects graph the last resolved instance will receive this callback first.
+  func didResolveDependencies()
+}
+
+extension Resolvable {
+  func resolveDependencies(_ container: DependencyContainer) {}
+  func didResolveDependencies() {}
+}
@@ -22,34 +22,128 @@
 // THE SOFTWARE.
 //

-// MARK: - Register/resolve dependencies with runtime arguments
-
 extension DependencyContainer {
  
+  /**
+   Register factory for type `T` and associate it with an optional tag.
+   
+   - parameters:
+      - scope: The scope to use for instance created by the factory. Default value is `Shared`.
+      - type: Type to register definition for. Default value is return value of factory.
+      - tag: The arbitrary tag to associate this factory with. Pass `nil` to associate with any tag. Default value is `nil`.
+      - factory: The factory that produces instance of `type`. Will be used to resolve instances of `type`.
+   
+   - returns: A registered definition.
+   
+   - note: You should cast the factory return type to the protocol you want to register it for
+           (unless you want to register concrete type) or provide `type` parameter.
+   
+   - seealso: `Definition`, `ComponentScope`, `DependencyTagConvertible`
+   
+   **Example**:
+   ```swift
+   //Register ServiceImp as Service
+   container.register { ServiceImp() as Service }
+   
+   //Register ServiceImp as Service named by "service"
+   container.register(tag: "service") { ServiceImp() as Service }
+   
+   //Register unique ServiceImp as Service
+   container.register(.unique) { ServiceImp() as Service }
+   
+   //Register ClientImp as Client and resolve it's service dependency
+   container.register { try ClientImp(service: container.resolve() as Service) as Client }
+   
+   //Register ServiceImp as concrete type
+   container.register { ServiceImp() }
+   container.register(factory: ServiceImp.init)
+   
+   //Register ServiceImp as Service
+   container.register(Service.self, factory: ServiceImp.init)
+   
+   //Register ClientImp as Client
+   container.register(Client.self, factory: ClientImp.init(service:))
+   ```
+   */
+  @discardableResult public func register<T>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping (()) throws -> T) -> Definition<T, ()> {
+    let definition = DefinitionBuilder<T, ()> {
+      $0.scope = scope
+      $0.factory = factory
+      }.build()
+    register(definition, tag: tag)
+    return definition
+  }
+  
+  /**
+   Register generic factory and auto-wiring factory and associate it with an optional tag.
+   
+   - parameters:
+      - tag: The arbitrary tag to associate this factory with. Pass `nil` to associate with any tag. Default value is `nil`.
+      - scope: The scope to use for instance created by the factory.
+      - factory: The factory to register.
+      - numberOfArguments: The number of factory arguments. Will be used on auto-wiring to sort definitions.
+      - autoWiringFactory: The factory to be used on auto-wiring to resolve component.
+   
+   - returns: A registered definition.
+   
+   - note: You _should not_ call this method directly, instead call any of other `register` methods.
+           You _should_ use this method only to register dependency with more runtime arguments
+           than _Dip_ supports (currently it's up to six) like in the following example:
+   
+   ```swift
+   public func register<T, A, B, C, ...>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: Tag? = nil, factory: (A, B, C, ...) throws -> T) -> Definition<T, (A, B, C, ...)> {
+     return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: ...) { container, tag in
+       try factory(container.resolve(tag: tag), ...)
+     }
+   }
+   ```
+   
+   Though before you do so you should probably review your design and try to reduce number of depnedencies.
+   */
+  public func register<T, U>(scope: ComponentScope, type: T.Type, tag: DependencyTagConvertible?, factory: @escaping (U) throws -> T, numberOfArguments: Int, autoWiringFactory: @escaping (DependencyContainer, Tag?) throws -> T) -> Definition<T, U> {
+    let definition = DefinitionBuilder<T, U> {
+      $0.scope = scope
+      $0.factory = factory
+      $0.numberOfArguments = numberOfArguments
+      $0.autoWiringFactory = autoWiringFactory
+      }.build()
+    register(definition, tag: tag)
+    return definition
+  }
+  
  // MARK: 1 Runtime Argument
  
  /**
-  Register factory that accepts one runtime argumentof type `Arg1`. You can use up to six runtime arguments.
+  Register factory that accepts one runtime argument of type `A`. You can use up to six runtime arguments.

  - note: You can have several factories with different number or types of arguments registered for same type,
          optionally associated with some tags. When container resolves that type it matches the type,
-          __number__, __types__ and __order__ of runtime arguments and optional tag that you pass to `resolve(tag:withArguments:)` method.
+          __number__, __types__ and __order__ of runtime arguments and optional tag that you pass to `resolve(tag:arguments:)` method.

  - parameters:
    - tag: The arbitrary tag to associate this factory with. Pass `nil` to associate with any tag. Default value is `nil`.
-    - scope: The scope to use for this component. Default value is `.Prototype`.
+    - scope: The scope to use for this component. Default value is `Shared`.
    - factory: The factory to register.
  
-  - seealso: `registerFactory(tag:scope:factory:)`
+  - seealso: `register(_:type:tag:factory:)`
  */
-  public func register<T, Arg1>(tag tag: DependencyTagConvertible? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1) throws -> T) -> DefinitionOf<T, (Arg1) throws -> T> {
-    return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: 1) { container, tag in try factory(try container.resolve(tag: tag)) }
+  @discardableResult public func register<T, A>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping ((A)) throws -> T) -> Definition<T, A> {
+    return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 1) { container, tag in try factory(container.resolve(tag: tag)) }
  }
-  
+
  /**
-   Resolve a dependency using one runtime argument.
+   Resolve type `T` using one runtime argument.
   
-   - note: When resolving type container will first try to use definition that matches types of arguments that you pass to resolve method. If it fails or no such definition is found container will try to _auto-wire_ component. For that it will iterate through all the definitions registered for that type which factories accept any number of runtime arguments and are tagged with the same tag, passed to `resolve` method, or with no tag. Container will try to use these definitions to resolve a component one by one until one of them succeeds, starting with tagged definitions in order of decreasing their's factories number of arguments.
+   - note: When resolving a type container will first try to use definition 
+           that exactly matches types of arguments that you pass to resolve method. 
+           If it fails or no such definition is found container will try to _auto-wire_ component. 
+           For that it will iterate through all the definitions registered for that type
+           which factories accept any number of runtime arguments and are tagged with the same tag,
+           passed to `resolve` method, or with no tag. Container will try to use these definitions
+           to resolve a component one by one until one of them succeeds, starting with tagged definitions
+           in order of decreasing their's factories number of arguments. If none of them succeds it will
+           throw an error. If it finds two definitions with the same number of arguments - it will throw
+           an error.
   
   - parameters:
      - tag: The arbitrary tag to lookup registered definition.
@@ -59,71 +153,101 @@ extension DependencyContainer {

   - returns: An instance of type `T`.

-   - seealso: `register(tag:_:factory:)`, `resolve(tag:builder:)`
+   - seealso: `register(_:type:tag:factory:)`, `resolve(tag:builder:)`
   */
-  public func resolve<T, Arg1>(tag tag: DependencyTagConvertible? = nil, withArguments arg1: Arg1) throws -> T {
-    return try resolve(tag: tag) { (factory: (Arg1) throws -> T) in try factory(arg1) }
-  }
-  
-  // MARK: 2 Runtime Arguments
-  
-  /// - seealso: `register(tag:scope:factory:)`
-  public func register<T, Arg1, Arg2>(tag tag: DependencyTagConvertible? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1, Arg2) throws -> T) -> DefinitionOf<T, (Arg1, Arg2) throws -> T> {
-    return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: 2) { container, tag in try factory(try container.resolve(tag: tag), try container.resolve(tag: tag)) }
-  }
-  
-  /// - seealso: `resolve(tag:_:)`
-  public func resolve<T, Arg1, Arg2>(tag tag: DependencyTagConvertible? = nil, withArguments arg1: Arg1, _ arg2: Arg2) throws -> T {
-    return try resolve(tag: tag) { (factory: (Arg1, Arg2) throws -> T) in try factory(arg1, arg2) }
+  public func resolve<T, A>(tag: DependencyTagConvertible? = nil, arguments arg1: A) throws -> T {
+    return try resolve(tag: tag) { factory in try factory(arg1) }
  }

+  ///- seealso: `resolve(_:tag:)`, `resolve(tag:arguments:)`
+  public func resolve<A>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, arguments arg1: A) throws -> Any {
+    return try resolve(type, tag: tag) { factory in try factory(arg1) }
+  }
+
+  // MARK: 2 Runtime Arguments
+  
+  /// - seealso: `register(_:type:tag:factory:)`
+  @discardableResult public func register<T, A, B>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping ((A, B)
+    ) throws -> T) -> Definition<T, (A, B)> {
+    return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 2) { container, tag in try factory((container.resolve(tag: tag), container.resolve(tag: tag))) }
+  }
+
+  /// - seealso: `resolve(tag:arguments:)`
+  public func resolve<T, A, B>(tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B) throws -> T {
+    return try resolve(T.self, tag: tag) { factory in try factory((arg1, arg2)) } as! T
+  }
+  
+  ///- seealso: `resolve(_:tag:)`, `resolve(tag:arguments:)`
+  public func resolve<A, B>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B) throws -> Any {
+    return try resolve(type, tag: tag) { factory in try factory((arg1, arg2)) }
+  }
+  
  // MARK: 3 Runtime Arguments
  
-  /// - seealso: `register(tag:scope:factory:)`
-  public func register<T, Arg1, Arg2, Arg3>(tag tag: DependencyTagConvertible? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3) throws -> T> {
-    return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: 3)  { container, tag in try factory(try container.resolve(tag: tag), try container.resolve(), try container.resolve(tag: tag)) }
+  /// - seealso: `register(_:type:tag:factory:)`
+  @discardableResult public func register<T, A, B, C>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping ((A, B, C)) throws -> T) -> Definition<T, (A, B, C)> {
+    return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 3)  { container, tag in try factory((container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag))) }
+  }
+
+  /// - seealso: `resolve(tag:arguments:)`
+  public func resolve<T, A, B, C>(tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C) throws -> T {
+    return try resolve(T.self, tag: tag) { factory in try factory((arg1, arg2, arg3)) } as! T
  }
  
-  /// - seealso: `resolve(tag:withArguments:)`
-  public func resolve<T, Arg1, Arg2, Arg3>(tag tag: DependencyTagConvertible? = nil, withArguments arg1: Arg1, _ arg2: Arg2, _ arg3: Arg3) throws -> T {
-    return try resolve(tag: tag) { (factory: (Arg1, Arg2, Arg3) throws -> T) in try factory(arg1, arg2, arg3) }
+  ///- seealso: `resolve(_:tag:)`, `resolve(tag:arguments:)`
+  public func resolve<A, B, C>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C) throws -> Any {
+    return try resolve(type, tag: tag) { factory in try factory((arg1, arg2, arg3)) }
  }
-  
+
  // MARK: 4 Runtime Arguments
  
-  /// - seealso: `register(tag:scope:factory:)`
-  public func register<T, Arg1, Arg2, Arg3, Arg4>(tag tag: DependencyTagConvertible? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3, Arg4) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3, Arg4) throws -> T> {
-    return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: 4) { container, tag in try factory(try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag)) }
+  /// - seealso: `register(_:type:tag:factory:)`
+  @discardableResult public func register<T, A, B, C, D>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping ((A, B, C, D)) throws -> T) -> Definition<T, (A, B, C, D)> {
+    return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 4) { container, tag in try factory((container.resolve(tag: tag),  container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag))) }
  }
-  
-  /// - seealso: `resolve(tag:withArguments:)`
-  public func resolve<T, Arg1, Arg2, Arg3, Arg4>(tag tag: DependencyTagConvertible? = nil, withArguments arg1: Arg1, _ arg2: Arg2, _ arg3: Arg3, _ arg4: Arg4) throws -> T {
-    return try resolve(tag: tag) { (factory: (Arg1, Arg2, Arg3, Arg4) throws -> T) in try factory(arg1, arg2, arg3, arg4) }
+
+  /// - seealso: `resolve(tag:arguments:)`
+  public func resolve<T, A, B, C, D>(tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C, _ arg4: D) throws -> T {
+    return try resolve(T.self, tag: tag) { factory in try factory((arg1, arg2, arg3, arg4)) } as! T
+  }
+
+  /// - seealso: `resolve(_:tag:)`, `resolve(tag:arguments:)`
+  public func resolve<A, B, C, D>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C, _ arg4: D) throws -> Any {
+    return try resolve(type, tag: tag) { factory in try factory((arg1, arg2, arg3, arg4)) }
  }

  // MARK: 5 Runtime Arguments
  
-  /// - seealso: `register(tag:scope:factory:)`
-  public func register<T, Arg1, Arg2, Arg3, Arg4, Arg5>(tag tag: DependencyTagConvertible? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3, Arg4, Arg5) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3, Arg4, Arg5) throws -> T> {
-    return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: 5) { container, tag in try factory(try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag)) }
+  /// - seealso: `register(_:type:tag:factory:)`
+  @discardableResult public func register<T, A, B, C, D, E>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping ((A, B, C, D, E)) throws -> T) -> Definition<T, (A, B, C, D, E)> {
+    return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 5) { container, tag in try factory((container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag))) }
  }
-  
-  /// - seealso: `resolve(tag:withArguments:)`
-  public func resolve<T, Arg1, Arg2, Arg3, Arg4, Arg5>(tag tag: DependencyTagConvertible? = nil, withArguments arg1: Arg1, _ arg2: Arg2, _ arg3: Arg3, _ arg4: Arg4, _ arg5: Arg5) throws -> T {
-    return try resolve(tag: tag) { (factory: (Arg1, Arg2, Arg3, Arg4, Arg5) throws -> T) in try factory(arg1, arg2, arg3, arg4, arg5) }
+
+  /// - seealso: `resolve(tag:arguments:)`
+  public func resolve<T, A, B, C, D, E>(tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C, _ arg4: D, _ arg5: E) throws -> T {
+    return try resolve(T.self, tag: tag) { factory in try factory((arg1, arg2, arg3, arg4, arg5)) } as! T
+  }
+
+  ///- seealso: `resolve(_:tag:)`, `resolve(tag:arguments:)`
+  public func resolve<A, B, C, D, E>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C, _ arg4: D, _ arg5: E) throws -> Any {
+    return try resolve(type, tag: tag) { factory in try factory((arg1, arg2, arg3, arg4, arg5)) }
  }

  // MARK: 6 Runtime Arguments
  
-  /// - seealso: `register(tag:scope:factory:)`
-  public func register<T, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6>(tag tag: DependencyTagConvertible? = nil, _ scope: ComponentScope = .Prototype, factory: (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6) throws -> T) -> DefinitionOf<T, (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6) throws -> T> {
-    return registerFactory(tag: tag, scope: scope, factory: factory, numberOfArguments: 6) { container, tag in try factory(try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag), try container.resolve(tag: tag)) }
+  /// - seealso: `register(_:type:tag:factory:)`
+  @discardableResult public func register<T, A, B, C, D, E, F>(_ scope: ComponentScope = .shared, type: T.Type = T.self, tag: DependencyTagConvertible? = nil, factory: @escaping ((A, B, C, D, E, F)) throws -> T) -> Definition<T, (A, B, C, D, E, F)> {
+    return register(scope: scope, type: type, tag: tag, factory: factory, numberOfArguments: 6) { container, tag in try factory((container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag), container.resolve(tag: tag))) }
  }
-  
-  /// - seealso: `resolve(tag:withArguments:)`
-  public func resolve<T, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6>(tag tag: DependencyTagConvertible? = nil, withArguments arg1: Arg1, _ arg2: Arg2, _ arg3: Arg3, _ arg4: Arg4, _ arg5: Arg5, _ arg6: Arg6) throws -> T {
-    return try resolve(tag: tag) { (factory: (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6) throws -> T) in try factory(arg1, arg2, arg3, arg4, arg5, arg6) }
+
+  /// - seealso: `resolve(tag:arguments:)`
+  public func resolve<T, A, B, C, D, E, F>(tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C, _ arg4: D, _ arg5: E, _ arg6: F) throws -> T {
+    return try resolve(T.self, tag: tag) { factory in try factory((arg1, arg2, arg3, arg4, arg5, arg6)) } as! T
+  }
+
+  /// - seealso: `resolve(_:tag:)`, `resolve(tag:arguments:)`
+  public func resolve<A, B, C, D, E, F>(_ type: Any.Type, tag: DependencyTagConvertible? = nil, arguments arg1: A, _ arg2: B, _ arg3: C, _ arg4: D, _ arg5: E, _ arg6: F) throws -> Any {
+    return try resolve(type, tag: tag) { factory in try factory((arg1, arg2, arg3, arg4, arg5, arg6)) }
  }

 }
-
@@ -0,0 +1,143 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+protocol TypeForwardingDefinition: DefinitionType {
+  var implementingTypes: [Any.Type] { get }
+  func doesImplements(type aType: Any.Type) -> Bool
+}
+
+extension Definition {
+  
+  /**
+   Registers definition for passed type.
+   
+   If instance created by factory of definition on which method is called 
+   does not implement type passed in a `type` parameter,
+   container will throw `DipError.DefinitionNotFound` error when trying to resolve that type.
+   
+   - parameters:
+      - type: Type to register definition for
+      - tag: Optional tag to associate definition with. Default is `nil`.
+   
+   - returns: definition on which `implements` was called
+   */
+  @discardableResult public func implements<F>(_ type: F.Type, tag: DependencyTagConvertible? = nil) -> Definition {
+    precondition(container != nil, "Definition should be registered in the container.")
+
+    container!.register(self, type: type, tag: tag)
+    return self
+  }
+  
+  /**
+   Registers definition for passed type.
+   
+   If instance created by factory of definition on which method is called
+   does not implement type passed in a `type` parameter,
+   container will throw `DipError.DefinitionNotFound` error when trying to resolve that type.
+   
+   - parameters:
+      - type: Type to register definition for
+      - tag: Optional tag to associate definition with. Default is `nil`.
+      - resolvingProperties: Optional block to be called to resolve instance property dependencies
+   
+   - returns: definition on which `implements` was called
+   */
+  @discardableResult public func implements<F>(_ type: F.Type, tag: DependencyTagConvertible? = nil, resolvingProperties: @escaping (DependencyContainer, F) throws -> ()) -> Definition {
+    precondition(container != nil, "Definition should be registered in the container.")
+
+    let forwardDefinition = container!.register(self, type: type, tag: tag)
+    forwardDefinition.resolvingProperties(resolvingProperties)
+    return self
+  }
+
+  ///Registers definition for types passed as parameters
+  @discardableResult public func implements<A, B>(_ a: A.Type, _ b: B.Type) -> Definition {
+    return implements(a).implements(b)
+  }
+
+  ///Registers definition for types passed as parameters
+  @discardableResult public func implements<A, B, C>(_ a: A.Type, _ b: B.Type, _ c: C.Type) -> Definition {
+    return implements(a).implements(b).implements(c)
+  }
+
+  ///Registers definition for types passed as parameters
+  @discardableResult public func implements<A, B, C, D>(_ a: A.Type, _ b: B.Type, _ c: C.Type, _ d: D.Type) -> Definition {
+    return implements(a).implements(b).implements(c).implements(d)
+  }
+  
+}
+
+extension DependencyContainer {
+  
+  func _register<T, U, F>(definition aDefinition: Definition<T, U>, type: F.Type, tag: DependencyTagConvertible? = nil) -> Definition<F, U> {
+    let definition = aDefinition
+    precondition(definition.container === self, "Definition should be registered in the container.")
+    
+    let key = DefinitionKey(type: F.self, typeOfArguments: U.self)
+    
+    let forwardDefinition = DefinitionBuilder<F, U> {
+      $0.scope = definition.scope
+      
+      let factory = definition.factory
+      $0.factory = { [unowned self] in
+        let resolved = try factory($0)
+        if let resolved = resolved as? F {
+          return resolved
+        }
+        else {
+          throw DipError.invalidType(resolved: resolved, key: key.tagged(with: self.context.tag))
+        }
+      }
+
+      $0.numberOfArguments = definition.numberOfArguments
+      $0.autoWiringFactory = definition.autoWiringFactory.map({ factory in
+        { [unowned self] in
+          let resolved = try factory($0, $1)
+          if let resolved = resolved as? F {
+            return resolved
+          }
+          else {
+            throw DipError.invalidType(resolved: resolved, key: key.tagged(with: self.context.tag))
+          }
+        }
+      })
+      $0.forwardsTo = definition
+      }.build()
+    
+    register(forwardDefinition, tag: tag)
+    return forwardDefinition
+  }
+  
+  /// Searches for definition that forwards requested type
+  func typeForwardingDefinition(forKey key: DefinitionKey) -> KeyDefinitionPair? {
+    var forwardingDefinitions = self.definitions.map({ (key: $0.0, definition: $0.1) })
+    
+    forwardingDefinitions = filter(definitions: forwardingDefinitions, byKey: key, byTypeOfArguments: true)
+    forwardingDefinitions = order(definitions: forwardingDefinitions, byTag: key.tag)
+
+    //we need to carry on original tag
+    return forwardingDefinitions.first.map({ ($0.key.tagged(with: key.tag), $0.definition) })
+  }
+  
+}
@@ -22,6 +22,68 @@
 // THE SOFTWARE.
 //

+public enum LogLevel: Int {
+  case None
+  case Errors
+  case Verbose
+}
+
+public var logLevel: LogLevel = .Errors
+
+public var logger: (LogLevel, Any) -> Void = { print($1) }
+
+func log(level logLevel: LogLevel, _ message: Any) {
+  guard logLevel.rawValue <= Dip.logLevel.rawValue else { return }
+  logger(logLevel, message)
+}
+
+///Internal protocol used to unwrap optional values.
+protocol BoxType {
+  var unboxed: Any? { get }
+}
+
+extension Optional: BoxType {
+  var unboxed: Any? {
+    return self ?? nil
+  }
+}
+
+extension ImplicitlyUnwrappedOptional: BoxType {
+  var unboxed: Any? {
+    return self ?? nil
+  }
+}
+
+class Box<T> {
+  var unboxed: T
+  init(_ value: T) {
+    self.unboxed = value
+  }
+}
+
+protocol WeakBoxType {
+  var unboxed: AnyObject? { get }
+}
+
+class WeakBox<T>: WeakBoxType {
+  weak var unboxed: AnyObject?
+  var value: T? {
+    return unboxed as? T
+  }
+
+  init(_ value: T) {
+    #if _runtime(_ObjC)
+      weak var value: AnyObject? = value as AnyObject
+    #else
+      weak var value: AnyObject? = value as? AnyObject
+    #endif
+    guard value != nil else {
+      fatalError("Can not store weak reference to not a class instance (\(T.self))")
+    }
+    self.unboxed = value
+  }
+}
+
 extension Dictionary {
  subscript(key: Key?) -> Value? {
    get {
@@ -41,7 +103,7 @@ extension Optional {
  }
 }

-#if os(Linux)
+#if !_runtime(_ObjC)
  import Glibc
  class RecursiveLock {
    private var _lock = _initializeRecursiveMutex()
@@ -71,7 +133,7 @@ extension Optional {
  
  extension pthread_mutex_t {
    mutating func lock() {
-      pthread_mutex_trylock(&self)
+      pthread_mutex_lock(&self)
    }
    mutating func unlock() {
      pthread_mutex_unlock(&self)
@@ -26,15 +26,13 @@ import XCTest
@testable import Dip

 private protocol Server: class {
-  weak var client: Client? {get}
-  var anotherClient: Client? {get set}
-  var optionalProperty: AnyObject? {get}
+  weak var client: Client! {get}
+  var anotherClient: Client! {get set}
 }

 private protocol Client: class {
  var server: Server? {get}
-  var anotherServer: Server? {get set}
-  var optionalProperty: AnyObject? {get}
+  var anotherServer: Server! {get set}
 }

 private class ServerImp: Server {
@@ -42,14 +40,14 @@ private class ServerImp: Server {
  var _client = InjectedWeak<Client>() { _ in
    AutoInjectionTests.clientDidInjectCalled = true
  }
-  var client: Client? {
+
+  var client: Client! {
    return _client.value
  }
  
-  weak var anotherClient: Client?
+  weak var anotherClient: Client!
  
  weak var _optionalProperty = InjectedWeak<AnyObject>(required: false)
-  var optionalProperty: AnyObject? { return _optionalProperty?.value }
 }

 private class ClientImp: Client {
@@ -57,16 +55,17 @@ private class ClientImp: Client {
  var _server = Injected<Server>() { _ in
    AutoInjectionTests.serverDidInjectCalled = true
  }
+
  var server: Server? {
    return _server.value
  }

-  var anotherServer: Server?
+  var anotherServer: Server!
  
  var _optionalProperty = Injected<AnyObject>(required: false)
-  var optionalProperty: AnyObject? { return _optionalProperty.value }
  
  var taggedServer = Injected<Server>(tag: "tagged")
+  var nilTaggedServer = Injected<Server>(tag: nil)
 }

 private class Obj1 {
@@ -94,10 +93,11 @@ class AutoInjectionTests: XCTestCase {

  let container = DependencyContainer()
  
-  #if os(Linux)
-  var allTests: [(String, () throws -> Void)] {
+  static var allTests = {
    return [
      ("testThatItResolvesAutoInjectedDependencies", testThatItResolvesAutoInjectedDependencies),
+      ("testThatItResolvesInheritedDependencies", testThatItResolvesInheritedDependencies),
+      ("testThatItCanSetInjectedProperty", testThatItCanSetInjectedProperty),
      ("testThatItThrowsErrorIfFailsToAutoInjectDependency", testThatItThrowsErrorIfFailsToAutoInjectDependency),
      ("testThatItResolvesAutoInjectedSingletons", testThatItResolvesAutoInjectedSingletons),
      ("testThatItCallsResolveDependencyBlockWhenAutoInjecting", testThatItCallsResolveDependencyBlockWhenAutoInjecting),
@@ -106,38 +106,70 @@ class AutoInjectionTests: XCTestCase {
      ("testThatThereIsNoRetainCycleBetweenAutoInjectedCircularDependencies", testThatThereIsNoRetainCycleBetweenAutoInjectedCircularDependencies),
      ("testThatItCallsDidInjectOnAutoInjectedProperty", testThatItCallsDidInjectOnAutoInjectedProperty),
      ("testThatNoErrorThrownWhenOptionalPropertiesAreNotAutoInjected", testThatNoErrorThrownWhenOptionalPropertiesAreNotAutoInjected),
-      ("testThatItResolvesTaggedAutoInjectedProperties", testThatItResolvesTaggedAutoInjectedProperties)
+      ("testThatItResolvesTaggedAutoInjectedProperties", testThatItResolvesTaggedAutoInjectedProperties),
+      ("testThatItPassesTagToAutoInjectedProperty", testThatItPassesTagToAutoInjectedProperty),
+      ("testThatItDoesNotPassTagToAutoInjectedPropertyWithExplicitTag", testThatItDoesNotPassTagToAutoInjectedPropertyWithExplicitTag),
+      ("testThatItAutoInjectsPropertyWithCollaboratingContainer", testThatItAutoInjectsPropertyWithCollaboratingContainer)
    ]
-  }
+  }()

-  func setUp() {
-    container.reset()
-  }
-  #else
  override func setUp() {
    container.reset()
  }
-  #endif

  func testThatItResolvesAutoInjectedDependencies() {
-    container.register(.ObjectGraph) { ServerImp() as Server }
-    container.register(.ObjectGraph) { ClientImp() as Client }
+    container.register { ServerImp() as Server }
+    container.register { ClientImp() as Client }
    
    let client = try! container.resolve() as Client
    let server = client.server
    XCTAssertTrue(client === server?.client)
  }
  
+  func testThatItResolvesInheritedDependencies() {
+    class ServerImp2: ServerImp {
+      var _client2 = InjectedWeak<Client>() { _ in
+        XCTAssertTrue(AutoInjectionTests.serverDidInjectCalled, "Inherited properties should be resolved first")
+      }
+      var client2: Client? { return _client2.value }
+    }
+
+    container.register { ServerImp2() as Server }
+    container.register { ClientImp() as Client }
+    
+    //when
+    let client = try! container.resolve() as Client
+    let server = client.server as? ServerImp2
+    XCTAssertTrue(client === server?.client)
+    XCTAssertTrue(client === server?.client2)
+  }
+  
+  func testThatItCanSetInjectedProperty() {
+    container.register { ServerImp() as Server }
+    container.register { ClientImp() as Client }
+    
+    let client = (try! container.resolve() as Client) as! ClientImp
+    let server = client.server as! ServerImp
+    
+    let newServer = ServerImp()
+    let newClient = ClientImp()
+    client._server = client._server.setValue(newServer)
+    server._client = server._client.setValue(newClient)
+    
+    XCTAssertTrue(client.server === newServer)
+    XCTAssertTrue(server.client === newClient)
+  }
+  
  func testThatItThrowsErrorIfFailsToAutoInjectDependency() {
-    container.register(.ObjectGraph) { ClientImp() as Client }
+    container.register { ClientImp() as Client }
    
    AssertThrows(expression: try container.resolve() as Client)
  }

  func testThatItResolvesAutoInjectedSingletons() {
    //given
-    container.register(.Singleton) { ServerImp() as Server }
-    container.register(.Singleton) { ClientImp() as Client }
+    container.register(.singleton) { ServerImp() as Server }
+    container.register(.singleton) { ClientImp() as Client }
    
    //when
    let sharedClient = try! container.resolve() as Client
@@ -156,34 +188,34 @@ class AutoInjectionTests: XCTestCase {
    var serverBlockWasCalled = false
    
    //given
-    container.register(.ObjectGraph) { ServerImp() as Server }
-      .resolveDependencies { (container, server) -> () in
+    container.register { ServerImp() as Server }
+      .resolvingProperties { (container, server) -> () in
        serverBlockWasCalled = true
    }

    var clientBlockWasCalled = false
-    container.register(.ObjectGraph) { ClientImp() as Client }
-      .resolveDependencies { (container, client) -> () in
+    container.register { ClientImp() as Client }
+      .resolvingProperties { (container, client) -> () in
        clientBlockWasCalled = true
    }

    //when
-    try! container.resolve() as Client
+    let _ = try! container.resolve() as Client
    XCTAssertTrue(serverBlockWasCalled)
    
-    try! container.resolve() as Server
+    let _ = try! container.resolve() as Server
    XCTAssertTrue(clientBlockWasCalled)
  }
  
  func testThatItReusesResolvedAutoInjectedInstances() {
    //given
-    container.register(.ObjectGraph) { ServerImp() as Server }
-      .resolveDependencies { (container, server) -> () in
+    container.register { ServerImp() as Server }
+      .resolvingProperties { (container, server) -> () in
        server.anotherClient = try! container.resolve() as Client
    }

-    container.register(.ObjectGraph) { ClientImp() as Client }
-      .resolveDependencies { (container, client) -> () in
+    container.register { ClientImp() as Client }
+      .resolvingProperties { (container, client) -> () in
        client.anotherServer = try! container.resolve() as Server
    }

@@ -205,9 +237,9 @@ class AutoInjectionTests: XCTestCase {
  
  func testThatItReusesAutoInjectedInstancesOnNextResolveOrAutoInjection() {
    //given
-    container.register(.ObjectGraph) { Obj1() }
-    container.register(.ObjectGraph) { Obj2() }
-    container.register(.ObjectGraph) { Obj3(obj: try self.container.resolve()) }
+    container.register { Obj1() }
+    container.register { Obj2() }
+    container.register { Obj3(obj: try self.container.resolve()) }
    
    //when
    let obj2 = try! container.resolve() as Obj2
@@ -222,8 +254,8 @@ class AutoInjectionTests: XCTestCase {
  
  func testThatThereIsNoRetainCycleBetweenAutoInjectedCircularDependencies() {
    //given
-    container.register(.ObjectGraph) { ServerImp() as Server }
-    container.register(.ObjectGraph) { ClientImp() as Client }
+    container.register { ServerImp() as Server }
+    container.register { ClientImp() as Client }

    //when
    var client: Client? = try! container.resolve() as Client
@@ -246,11 +278,11 @@ class AutoInjectionTests: XCTestCase {
    AutoInjectionTests.serverDidInjectCalled = false
    
    //given
-    container.register(.ObjectGraph) { ServerImp() as Server }
-    container.register(.ObjectGraph) { ClientImp() as Client }
+    container.register { ServerImp() as Server }
+    container.register { ClientImp() as Client }
    
    //when
-    try! container.resolve() as Client
+    let _ = try! container.resolve() as Client
    
    //then
    XCTAssertTrue(AutoInjectionTests.clientDidInjectCalled)
@@ -259,17 +291,17 @@ class AutoInjectionTests: XCTestCase {
  
  func testThatNoErrorThrownWhenOptionalPropertiesAreNotAutoInjected() {
    //given
-    container.register(.ObjectGraph) { ServerImp() as Server }
-    container.register(.ObjectGraph) { ClientImp() as Client }
+    container.register { ServerImp() as Server }
+    container.register { ClientImp() as Client }

    AssertNoThrow(expression: try container.resolve() as Client, "Container should not throw error if failed to resolve optional auto-injected properties.")
  }
  
  func testThatItResolvesTaggedAutoInjectedProperties() {
    //given
-    container.register(.ObjectGraph) { ServerImp() as Server }
-    container.register(tag: "tagged", .ObjectGraph) { ServerImp() as Server }
-    container.register(.ObjectGraph) { ClientImp() as Client }
+    container.register { ServerImp() as Server }
+    container.register(tag: "tagged") { ServerImp() as Server }
+    container.register { ClientImp() as Client }
    
    //when
    let client = try! container.resolve() as Client
@@ -280,6 +312,65 @@ class AutoInjectionTests: XCTestCase {
    
    //server and tagged server should be resolved as different instances
    XCTAssertTrue(server !== taggedServer)
+    XCTAssertNotNil(server)
+    XCTAssertNotNil(taggedServer)
+  }
+  
+  func testThatItPassesTagToAutoInjectedProperty() {
+    //given
+    container.register { ServerImp() as Server }
+    container.register(tag: "tagged") { ServerImp() as Server }
+    container.register { ClientImp() as Client }
+    
+    //when
+    let client = try! container.resolve(tag: "tagged") as Client
+    
+    //then
+    let taggedServer = (client as! ClientImp).taggedServer.value!
+    let server = client.server!
+    
+    //server and tagged server should be resolved as the same instance
+    XCTAssertTrue(server === taggedServer)
+  }
+  
+  func testThatItDoesNotPassTagToAutoInjectedPropertyWithExplicitTag() {
+    //given
+    container.register { ServerImp() as Server }
+    container.register(tag: "tagged") { ServerImp() as Server }
+
+    container.register { ClientImp() as Client }
+      .resolvingProperties { (container, client) -> () in
+        client.anotherServer = try! container.resolve() as Server
+    }
+
+    //when
+    let client = try! container.resolve(tag: "otherTag") as Client
+    
+    //then
+    let taggedServer = (client as! ClientImp).taggedServer.value!
+    let nilTaggedServer = (client as! ClientImp).nilTaggedServer.value!
+    let server = client.server!
+    
+    //server and tagged server should be resolved as different instances
+    XCTAssertTrue(server !== taggedServer)
+    XCTAssertTrue((client.anotherServer as! ServerImp) === nilTaggedServer)
+    
+    XCTAssertNotNil(server)
+    XCTAssertNotNil(taggedServer)
+    XCTAssertNotNil(nilTaggedServer)
+  }
+  
+  func testThatItAutoInjectsPropertyWithCollaboratingContainer() {
+    let collaborator = DependencyContainer()
+    collaborator.register { ServerImp() as Server }
+    container.register { ClientImp() as Client }
+    
+    container.collaborate(with: collaborator)
+    collaborator.collaborate(with: container)
+    
+    let client = try! container.resolve() as Client
+    let server = client.server
+    XCTAssertTrue(client === server?.client)
  }
  
 }
@@ -0,0 +1,484 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+import XCTest
+@testable import Dip
+
+private protocol Service: class { }
+private class ServiceImp1: Service { }
+private class ServiceImp2: Service { }
+private class ServiceImp3 {}
+
+private protocol AutoWiredClient: class {
+  var service1: Service! { get set }
+  var service2: Service! { get set }
+}
+
+private class AutoWiredClientImp: AutoWiredClient {
+  var service1: Service!
+  var service2: Service!
+  
+  init(service1: Service?, service2: ServiceImp2) {
+    self.service1 = service1
+    self.service2 = service2
+  }
+  init() {}
+}
+
+class AutoWiringTests: XCTestCase {
+  
+  let container = DependencyContainer()
+
+  static var allTests = {
+    return [
+      ("testThatItCanResolveWithAutoWiring", testThatItCanResolveWithAutoWiring),
+      ("testThatItUsesAutoWireFactoryWithMostNumberOfArguments", testThatItUsesAutoWireFactoryWithMostNumberOfArguments),
+      ("testThatItThrowsAmbiguityErrorWhenUsingAutoWire", testThatItThrowsAmbiguityErrorWhenUsingAutoWire),
+      ("testThatItUsesAutoWireFactoryWithMostNumberOfArguments", testThatItUsesAutoWireFactoryWithMostNumberOfArguments),
+      ("testThatItPrefersTaggedFactoryWithDifferentNumberOfArgumentsWhenUsingAutoWire", testThatItPrefersTaggedFactoryWithDifferentNumberOfArgumentsWhenUsingAutoWire),
+      ("testThatItPrefersTaggedFactoryWithDifferentTypesOfArgumentsWhenUsingAutoWire", testThatItPrefersTaggedFactoryWithDifferentTypesOfArgumentsWhenUsingAutoWire),
+      ("testThatItFallbackToNotTaggedFactoryWhenUsingAutoWire", testThatItFallbackToNotTaggedFactoryWhenUsingAutoWire),
+      ("testThatItDoesNotTryToUseAutoWiringWhenCallingResolveWithArguments", testThatItDoesNotTryToUseAutoWiringWhenCallingResolveWithArguments),
+      ("testThatItDoesNotUseAutoWiringWhenFailedToResolveLowLevelDependency", testThatItDoesNotUseAutoWiringWhenFailedToResolveLowLevelDependency),
+      ("testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgain", testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgain),
+      ("testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithTheSameTag", testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithTheSameTag),
+      ("testThatItDoesNotReuseInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithAnotherTag", testThatItDoesNotReuseInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithAnotherTag),
+      ("testThatItUsesTagToResolveDependenciesWithAutoWiringWith1Argument", testThatItUsesTagToResolveDependenciesWithAutoWiringWith1Argument),
+      ("testThatItUsesTagToResolveDependenciesWithAutoWiringWith2Arguments", testThatItUsesTagToResolveDependenciesWithAutoWiringWith2Arguments),
+      ("testThatItUsesTagToResolveDependenciesWithAutoWiringWith3Arguments", testThatItUsesTagToResolveDependenciesWithAutoWiringWith3Arguments),
+      ("testThatItUsesTagToResolveDependenciesWithAutoWiringWith4Arguments", testThatItUsesTagToResolveDependenciesWithAutoWiringWith4Arguments),
+      ("testThatItUsesTagToResolveDependenciesWithAutoWiringWith5Arguments", testThatItUsesTagToResolveDependenciesWithAutoWiringWith5Arguments),
+      ("testThatItUsesTagToResolveDependenciesWithAutoWiringWith6Arguments", testThatItUsesTagToResolveDependenciesWithAutoWiringWith6Arguments),
+      ("testThatItCanAutoWireOptional", testThatItCanAutoWireOptional)
+    ]
+  }()
+
+  override func setUp() {
+    container.reset()
+  }
+
+  func testThatItCanResolveWithAutoWiring() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+    
+    //when
+    let client = try! container.resolve() as AutoWiredClient
+    
+    //then
+    let service1 = client.service1
+    XCTAssertTrue(service1 is ServiceImp1)
+    let service2 = client.service2
+    XCTAssertTrue(service2 is ServiceImp2)
+    
+    //when
+    let anyClient = try! container.resolve(AutoWiredClient.self)
+    
+    //then
+    XCTAssertTrue(anyClient is AutoWiredClientImp)
+  }
+  
+  func testThatItUsesAutoWireFactoryWithMostNumberOfArguments() {
+    //given
+    
+    //1 arg
+    container.register { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
+    //1 arg
+    container.register { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }
+    
+    //2 args
+    var factoryWithMostNumberOfArgumentsCalled = false
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+      .resolvingProperties { _,_  in
+        factoryWithMostNumberOfArgumentsCalled = true
+    }
+    
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //when
+    let _ = try! container.resolve() as AutoWiredClient
+    
+    //then
+    XCTAssertTrue(factoryWithMostNumberOfArgumentsCalled)
+  }
+  
+  func testThatItThrowsAmbiguityErrorWhenUsingAutoWire() {
+    //given
+    
+    //1 arg
+    container.register { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
+    //1 arg
+    container.register { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }
+    
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //when
+    AssertThrows(expression: try container.resolve() as AutoWiredClient) { error -> Bool in
+      switch error {
+      case let DipError.autoWiringFailed(_, error):
+        if case DipError.ambiguousDefinitions = error { return true }
+        else { return false }
+      default: return false
+      }
+    }
+  }
+  
+  func testThatItPrefersTaggedFactoryWithDifferentNumberOfArgumentsWhenUsingAutoWire() {
+    //given
+    
+    //1 arg
+    container.register { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
+    //1 arg
+    container.register { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }
+    
+    //2 args
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+    
+    //1 arg tagged
+    var taggedFactoryWithMostNumberOfArgumentsCalled = false
+    container.register(tag: "tag") { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
+    
+    //2 arg tagged
+    container.register(tag: "tag") { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }.resolvingProperties { _,_  in
+      taggedFactoryWithMostNumberOfArgumentsCalled = true
+    }
+
+    container.register() { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as AutoWiredClient
+    
+    //then
+    XCTAssertTrue(taggedFactoryWithMostNumberOfArgumentsCalled)
+  }
+  
+  func testThatItPrefersTaggedFactoryWithDifferentTypesOfArgumentsWhenUsingAutoWire() {
+    //given
+    
+    //1 arg
+    container.register { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
+    
+    //2 args
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+    
+    //1 arg tagged
+    var taggedFactoryCalled = false
+    container.register(tag: "tag") { AutoWiredClientImp(service1: try self.container.resolve(), service2: $0) as AutoWiredClient }.resolvingProperties { _,_  in
+      taggedFactoryCalled = true
+    }
+    
+    container.register() { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as AutoWiredClient
+    
+    //then
+    XCTAssertTrue(taggedFactoryCalled)
+  }
+  
+  func testThatItFallbackToNotTaggedFactoryWhenUsingAutoWire() {
+    //given
+    
+    //1 arg
+    var notTaggedFactoryWithMostNumberOfArgumentsCalled = false
+    container.register { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }.resolvingProperties { _,_  in
+      notTaggedFactoryWithMostNumberOfArgumentsCalled = true
+    }
+    
+    //1 arg tagged
+    container.register(tag: "tag") { AutoWiredClientImp(service1: $0, service2: try self.container.resolve()) as AutoWiredClient }
+    
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //when
+    let _ = try! container.resolve(tag: "other tag") as AutoWiredClient
+    
+    //then
+    XCTAssertTrue(notTaggedFactoryWithMostNumberOfArgumentsCalled)
+  }
+  
+  func testThatItDoesNotTryToUseAutoWiringWhenCallingResolveWithArguments() {
+    //given
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //when
+    let service = try! container.resolve() as Service
+    AssertThrows(expression: try container.resolve(arguments: service) as AutoWiredClient,
+      "Container should not use auto-wiring when resolving with runtime arguments")
+  }
+  
+  func testThatItDoesNotUseAutoWiringWhenFailedToResolveLowLevelDependency() {
+    //given
+    container.register { AutoWiredClientImp() as AutoWiredClient }
+      .resolvingProperties { container, resolved in
+        resolved.service1 = try container.resolve() as Service
+        resolved.service2 = try container.resolve() as ServiceImp2
+        
+        //simulate that something goes wrong on the way
+        throw DipError.definitionNotFound(key: DefinitionKey(type: ServiceImp1.self, typeOfArguments: Any.self))
+    }
+    
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+      .resolvingProperties { container, resolved in
+        //auto-wiring should be performed only when definition for type to resolve is not found
+        //but not for any other type along the way in the graph
+        XCTFail("Auto-wiring should not be performed if instance was actually resolved.")
+    }
+    
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    //then
+    AssertThrows(expression: try container.resolve() as AutoWiredClient,
+      "Container should not use auto-wiring when definition for resolved type is registered.")
+  }
+  
+  func testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgain() {
+    
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    var anotherInstance: AutoWiredClient?
+    
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+      .resolvingProperties { container, _ in
+        if anotherInstance == nil {
+          anotherInstance = try! container.resolve() as AutoWiredClient
+        }
+    }
+    
+    //when
+    let resolved = try! container.resolve() as AutoWiredClient
+    
+    //then
+    //when doing another auto-wiring during resolve we should reuse instance
+    XCTAssertTrue((resolved as! AutoWiredClientImp) === (anotherInstance as! AutoWiredClientImp))
+  }
+  
+  func testThatItReusesInstancesResolvedWithoutAutoWiringWhenUsingAutoWiringAgain() {
+    
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    var anotherInstance: AutoWiredClient?
+    
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+      .resolvingProperties { container, _ in
+        if anotherInstance == nil {
+          anotherInstance = try! container.resolve() as AutoWiredClient
+        }
+    }
+    
+    //when
+    let service1 = try! container.resolve() as Service?
+    let service2 = try! container.resolve() as ServiceImp2
+    let resolved = try! container.resolve(arguments: service1, service2) as AutoWiredClient
+    
+    //then
+    //when doing another auto-wiring during resolve we should reuse instance
+    XCTAssertTrue((resolved as! AutoWiredClientImp) === (anotherInstance as! AutoWiredClientImp))
+  }
+
+  func testThatItReusesInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithTheSameTag() {
+    
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    var anotherInstance: AutoWiredClient?
+    
+    container.register(tag: "tag") { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+      .resolvingProperties { container, _ in
+        if anotherInstance == nil {
+          anotherInstance = try! container.resolve(tag: "tag") as AutoWiredClient
+        }
+    }
+    
+    //when
+    let resolved = try! container.resolve(tag: "tag") as AutoWiredClient
+    
+    //then
+    //when doing another auto-wiring during resolve we should reuse instance
+    XCTAssertTrue((resolved as! AutoWiredClientImp) === (anotherInstance as! AutoWiredClientImp))
+  }
+  
+  func testThatItDoesNotReuseInstancesResolvedWithAutoWiringWhenUsingAutoWiringAgainWithAnotherTag() {
+    
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    
+    var anotherInstance: AutoWiredClient?
+    
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+      .resolvingProperties { container, _ in
+        if anotherInstance == nil {
+          anotherInstance = try! container.resolve() as AutoWiredClient
+        }
+    }
+    
+    //when
+    let resolved = try! container.resolve(tag: "tag") as AutoWiredClient
+    
+    //then
+    //when doing another auto-wiring during resolve we should reuse instance
+    XCTAssertTrue((resolved as! AutoWiredClientImp) !== (anotherInstance as! AutoWiredClientImp))
+  }
+  
+  func testThatItUsesTagToResolveDependenciesWithAutoWiringWith1Argument() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register(tag: "tag") { ServiceImp2() as Service }
+    
+    container.register { (dep1: Service) -> ServiceImp3 in
+      XCTAssertTrue(dep1 is ServiceImp2)
+      return ServiceImp3()
+    }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as ServiceImp3
+  }
+
+  func testThatItUsesTagToResolveDependenciesWithAutoWiringWith2Arguments() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register(tag: "tag") { ServiceImp2() as Service }
+    
+    container.register { (dep1: Service, dep2: Service) -> ServiceImp3 in
+      XCTAssertTrue(dep1 is ServiceImp2)
+      XCTAssertTrue(dep2 is ServiceImp2)
+      return ServiceImp3()
+    }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as ServiceImp3
+  }
+
+  func testThatItUsesTagToResolveDependenciesWithAutoWiringWith3Arguments() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register(tag: "tag") { ServiceImp2() as Service }
+    
+    container.register { (dep1: Service, dep2: Service, dep3: Service) -> ServiceImp3 in
+      XCTAssertTrue(dep1 is ServiceImp2)
+      XCTAssertTrue(dep2 is ServiceImp2)
+      XCTAssertTrue(dep3 is ServiceImp2)
+      return ServiceImp3()
+    }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as ServiceImp3
+  }
+
+  func testThatItUsesTagToResolveDependenciesWithAutoWiringWith4Arguments() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register(tag: "tag") { ServiceImp2() as Service }
+    
+    container.register { (dep1: Service, dep2: Service, dep3: Service, dep4: Service) -> ServiceImp3 in
+      XCTAssertTrue(dep1 is ServiceImp2)
+      XCTAssertTrue(dep2 is ServiceImp2)
+      XCTAssertTrue(dep3 is ServiceImp2)
+      XCTAssertTrue(dep4 is ServiceImp2)
+      return ServiceImp3()
+    }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as ServiceImp3
+  }
+
+  func testThatItUsesTagToResolveDependenciesWithAutoWiringWith5Arguments() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register(tag: "tag") { ServiceImp2() as Service }
+    
+    container.register { (dep1: Service, dep2: Service, dep3: Service, dep4: Service, dep5: Service) -> ServiceImp3 in
+      XCTAssertTrue(dep1 is ServiceImp2)
+      XCTAssertTrue(dep2 is ServiceImp2)
+      XCTAssertTrue(dep3 is ServiceImp2)
+      XCTAssertTrue(dep4 is ServiceImp2)
+      XCTAssertTrue(dep5 is ServiceImp2)
+      return ServiceImp3()
+    }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as ServiceImp3
+  }
+
+  func testThatItUsesTagToResolveDependenciesWithAutoWiringWith6Arguments() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register(tag: "tag") { ServiceImp2() as Service }
+    
+    container.register { (dep1: Service, dep2: Service, dep3: Service, dep4: Service, dep5: Service, dep6: Service) -> ServiceImp3 in
+      XCTAssertTrue(dep1 is ServiceImp2)
+      XCTAssertTrue(dep2 is ServiceImp2)
+      XCTAssertTrue(dep3 is ServiceImp2)
+      XCTAssertTrue(dep4 is ServiceImp2)
+      XCTAssertTrue(dep5 is ServiceImp2)
+      XCTAssertTrue(dep6 is ServiceImp2)
+      return ServiceImp3()
+    }
+    
+    //when
+    let _ = try! container.resolve(tag: "tag") as ServiceImp3
+  }
+
+  func testThatItCanAutoWireOptional() {
+    //given
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp2() }
+    container.register { AutoWiredClientImp(service1: $0, service2: $1) as AutoWiredClient }
+    
+    var resolved: AutoWiredClient?
+    //when
+    AssertNoThrow(expression: resolved = try container.resolve() as AutoWiredClient?)
+    XCTAssertNotNil(resolved)
+    
+    //when
+    AssertNoThrow(expression: resolved = try container.resolve() as AutoWiredClient!)
+    XCTAssertNotNil(resolved)
+
+    //when
+    AssertNoThrow(expression: resolved = try container.resolve(tag: "tag") as AutoWiredClient?)
+    XCTAssertNotNil(resolved)
+    
+    //when
+    AssertNoThrow(expression: resolved = try container.resolve(tag: "tag") as AutoWiredClient!)
+    XCTAssertNotNil(resolved)
+  }
+  
+}
+
@@ -0,0 +1,377 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+import XCTest
+@testable import Dip
+
+private protocol Service: class {}
+private class ServiceImp1: Service {}
+private class ServiceImp2: Service {}
+
+private class Server {
+  weak var client: Client?
+  
+  init() {}
+}
+
+private class Client {
+  var server: Server
+  
+  init(server: Server) {
+    self.server = server
+  }
+}
+
+class ComponentScopeTests: XCTestCase {
+  
+  let container = DependencyContainer()
+  
+  static var allTests = {
+    return [
+      ("testThatSharedIsDefaultScope", testThatSharedIsDefaultScope),
+      ("testThatScopeCanBeChanged", testThatScopeCanBeChanged),
+      ("testThatItResolvesTypeAsNewInstanceForUniqueScope", testThatItResolvesTypeAsNewInstanceForUniqueScope),
+      ("testThatItReusesInstanceForSingletonScope", testThatItReusesInstanceForSingletonScope),
+      ("testThatSingletonIsNotReusedAcrossContainers", testThatSingletonIsNotReusedAcrossContainers),
+      ("testThatSingletonIsReleasedWhenDefinitionIsRemoved", testThatSingletonIsReleasedWhenDefinitionIsRemoved),
+      ("testThatSingletonIsReleasedWhenDefinitionIsOverridden", testThatSingletonIsReleasedWhenDefinitionIsOverridden),
+      ("testThatSingletonIsReleasedWhenContainerIsReset", testThatSingletonIsReleasedWhenContainerIsReset),
+      ("testThatItReusesInstanceInSharedScopeDuringResolve", testThatItReusesInstanceInSharedScopeDuringResolve),
+      ("testThatItDoesNotReuseInstanceInSharedScopeInNextResolve", testThatItDoesNotReuseInstanceInSharedScopeInNextResolve),
+      ("testThatItDoesNotReuseInstanceInSharedScopeResolvedForNilTag", testThatItDoesNotReuseInstanceInSharedScopeResolvedForNilTagWhenResolvingForAnotherTag),
+      ("testThatItReusesInstanceInSharedScopeResolvedForNilTag", testThatItReusesInstanceInSharedScopeResolvedForNilTag),
+      ("testThatItReusesResolvedInstanceWhenResolvingOptional", testThatItReusesResolvedInstanceWhenResolvingOptional),
+      ("testThatItHoldsWeakReferenceToWeakSingletonInstance", testThatItHoldsWeakReferenceToWeakSingletonInstance),
+      ("testThatItResolvesWeakSingletonAgainAfterItWasReleased", testThatItResolvesWeakSingletonAgainAfterItWasReleased),
+      ("testThatCollaboratingContainersReuseSingletonsResolvedByAnotherContainer", testThatCollaboratingContainersReuseSingletonsResolvedByAnotherContainer)
+    ]
+  }()
+  
+  override func setUp() {
+    container.reset()
+  }
+  
+  func testThatSharedIsDefaultScope() {
+    let def = container.register { ServiceImp1() as Service }
+    XCTAssertEqual(def.scope, ComponentScope.shared)
+  }
+  
+  func testThatScopeCanBeChanged() {
+    let def = container.register(.singleton) { ServiceImp1() as Service }
+    XCTAssertEqual(def.scope, ComponentScope.singleton)
+  }
+  
+  func testThatItResolvesTypeAsNewInstanceForUniqueScope() {
+    //given
+    container.register { ServiceImp1() as Service }
+    
+    //when
+    let service1 = try! container.resolve() as Service
+    let service2 = try! container.resolve() as Service
+    
+    //then
+    XCTAssertFalse(service1 === service2)
+  }
+  
+  func testThatItReusesInstanceForSingletonScope() {
+    func test(_ scope: ComponentScope, line: UInt = #line) {
+      //given
+      container.register(scope) { ServiceImp1() as Service }
+      
+      //when
+      let service1 = try! container.resolve() as Service
+      let service2 = try! container.resolve() as Service
+      
+      //then
+      XCTAssertTrue(service1 === service2, line: line)
+    }
+    
+    test(.singleton)
+    test(.weakSingleton)
+    test(.eagerSingleton)
+  }
+  
+  func testThatSingletonIsNotReusedAcrossContainers() {
+    func test(_ scope: ComponentScope, line: UInt = #line) {
+      //given
+      let def = container.register(scope) { ServiceImp1() as Service }
+      let secondContainer = DependencyContainer()
+      secondContainer.register(def, tag: nil)
+      
+      //when
+      let service1 = try! container.resolve() as Service
+      let service2 = try! secondContainer.resolve() as Service
+      
+      //then
+      XCTAssertTrue(service1 !== service2, "Singleton instances should not be reused across containers", line: line)
+    }
+    
+    test(.singleton)
+    test(.weakSingleton)
+    test(.eagerSingleton)
+  }
+  
+  func testThatSingletonIsReleasedWhenDefinitionIsRemoved() {
+    func test(_ scope: ComponentScope, line: UInt = #line) {
+      //given
+      let def = container.register(scope) { ServiceImp1() as Service }
+      let service1 = try! container.resolve() as Service
+      
+      //when
+      container.remove(def, tag: nil)
+      container.register(def, tag: nil)
+      
+      //then
+      let service2 = try! container.resolve() as Service
+      XCTAssertTrue(service1 !== service2, "Singleton instances should be released when definition is removed from the container", line: line)
+    }
+    
+    test(.singleton)
+    test(.weakSingleton)
+    test(.eagerSingleton)
+  }
+  
+  func testThatSingletonIsReleasedWhenDefinitionIsOverridden() {
+    func test(_ scope: ComponentScope, line: UInt = #line) {
+      //given
+      let def = container.register(scope) { ServiceImp1() as Service }
+      let service1 = try! container.resolve() as Service
+      
+      //when
+      container.register(def, tag: nil)
+      
+      //then
+      let service2 = try! container.resolve() as Service
+      XCTAssertTrue(service1 !== service2, "Singleton instances should be released when definition is overridden", line: line)
+    }
+    
+    test(.singleton)
+    test(.weakSingleton)
+    test(.eagerSingleton)
+  }
+  
+  func testThatSingletonIsReleasedWhenContainerIsReset() {
+    func test(_ scope: ComponentScope, line: UInt = #line) {
+      //given
+      let def = container.register(scope) { ServiceImp1() as Service }
+      let service1 = try! container.resolve() as Service
+      
+      //when
+      container.reset()
+      container.register(def, tag: nil)
+      
+      //then
+      let service2 = try! container.resolve() as Service
+      XCTAssertTrue(service1 !== service2, "Singleton instances should be released when container is reset", line: line)
+    }
+    
+    test(.singleton)
+    test(.weakSingleton)
+    test(.eagerSingleton)
+  }
+  
+  func testThatItReusesInstanceInSharedScopeDuringResolve() {
+    //given
+    container.register { Client(server: try self.container.resolve()) as Client }
+    
+    container.register { Server() as Server }
+      .resolvingProperties { container, server in
+        server.client = try container.resolve() as Client
+    }
+    
+    //when
+    let client = try! container.resolve() as Client
+    
+    //then
+    let server = client.server
+    XCTAssertTrue(server.client === client)
+  }
+  
+  func testThatItDoesNotReuseInstanceInSharedScopeInNextResolve() {
+    //given
+    container.register { Client(server: try self.container.resolve()) as Client }
+    container.register { Server() as Server }
+      .resolvingProperties { container, server in
+        server.client = try container.resolve() as Client
+    }
+    
+    //when
+    let client = try! container.resolve() as Client
+    let server = client.server
+    
+    let anotherClient = try! container.resolve() as Client
+    let anotherServer = anotherClient.server
+    
+    //then
+    XCTAssertFalse(server === anotherServer)
+    XCTAssertFalse(client === anotherClient)
+  }
+
+  func testThatItDoesNotReuseInstanceInSharedScopeResolvedForNilTagWhenResolvingForAnotherTag() {
+    //given
+    var service2: Service?
+    container.register { ServiceImp1() as Service }
+      .resolvingProperties { (c, _) in
+        //when service1 is resolved using this definition due to fallback to nil tag
+        service2 = try c.resolve(tag: "service") as Service
+        
+        //then we don't want every next resolve of service for other tags to reuse it
+        XCTAssertTrue(service2 is ServiceImp2)
+    }
+    container.register(tag: "service") { ServiceImp2() as Service}
+    
+    //when
+    let service1 = try! container.resolve(tag: "tag") as Service
+
+    //then
+    XCTAssertTrue(service1 is ServiceImp1)
+  }
+  
+  func testThatItReusesInstanceInSharedScopeResolvedForNilTag() {
+    //given
+    var service2: Service?
+    container.register { ServiceImp1() as Service }
+      .resolvingProperties { (c, service1) in
+        guard service2 == nil else { return }
+        
+        //when service1 is resolved using this definition due to fallback to nil tag
+        //and service is resolved again with another (existing) tag
+        service2 = try c.resolve(tag: "tag") as Service
+        
+        //than we don't want every next resolve of service to reuse it
+        XCTAssertTrue(service1 as! ServiceImp1 === service1)
+    }
+    
+    //when
+    let service1 = try! container.resolve(tag: "tag") as Service
+    
+    //then
+    XCTAssertTrue(service1 is ServiceImp1)
+  }
+  
+  func testThatOnlyEagerSingletonIsCreatedWhenContainerIsBootsrapped() {
+    //given
+    var eagerSingletonResolved = false
+    
+    container.register(.eagerSingleton, tag: "eager") { ServiceImp1() as Service }
+      .resolvingProperties { container, service in eagerSingletonResolved = true }
+    
+    container.register(.singleton, tag: "singleton") { ServiceImp1() as Service }
+      .resolvingProperties { container, service in XCTFail() }
+
+    container.register(.unique, tag: "prototype") { ServiceImp1() as Service }
+      .resolvingProperties { container, service in XCTFail() }
+
+    container.register(.shared, tag: "graph") { ServiceImp1() as Service }
+      .resolvingProperties { container, service in XCTFail() }
+    
+    //when
+    try! container.bootstrap()
+    XCTAssertTrue(eagerSingletonResolved)
+  }
+  
+  func testThatContainerCanBeBootstrappedAgainAfterReset() {
+    try! container.bootstrap()
+    XCTAssertTrue(container.bootstrapped)
+    
+    container.reset()
+    XCTAssertFalse(container.bootstrapped)
+  }
+  
+  func testThatItReusesResolvedInstanceWhenResolvingOptional() {
+    var otherService: Service!
+    var impOtherService: Service!
+    var anyOtherService: Any!
+    var anyImpOtherService: Any!
+    
+    container.register { ServiceImp1() as Service }
+      .resolvingProperties { container, service in
+        otherService = try! container.resolve() as Service?
+        impOtherService = try! container.resolve() as Service!
+        anyOtherService = try! container.resolve((Service?).self)
+        anyImpOtherService = try! container.resolve((Service!).self)
+    }
+    
+    let service = try! container.resolve() as Service
+    XCTAssertTrue(otherService as! ServiceImp1 === service as! ServiceImp1)
+    XCTAssertTrue(impOtherService as! ServiceImp1 === service as! ServiceImp1)
+    XCTAssertTrue(anyOtherService as! ServiceImp1 === service as! ServiceImp1)
+    XCTAssertTrue(anyImpOtherService as! ServiceImp1 === service as! ServiceImp1)
+  }
+  
+  func testThatItHoldsWeakReferenceToWeakSingletonInstance() {
+    //given
+    container.register(.weakSingleton) { ServiceImp1() as Service }
+    var strongSingleton: Service? = try! container.resolve() as Service
+    weak var weakSingleton = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(weakSingleton === strongSingleton)
+    
+    //when
+    strongSingleton = nil
+    
+    //then
+    XCTAssertNil(weakSingleton)
+  }
+  
+  func testThatItResolvesWeakSingletonAgainAfterItWasReleased() {
+    Dip.logLevel = .Verbose
+    //given
+    let service = container.register(.weakSingleton) { ServiceImp1() }
+    container.register(service, type: Service.self)
+    
+    //when
+    //resolve and realease reight away
+    _ = try? container.resolve() as ServiceImp1
+    
+    //then
+    AssertNoThrow(expression: try container.resolve() as Service, "Weak singleton should be resolved again.")
+  }
+  
+  func testThatCollaboratingContainersReuseSingletonsResolvedByAnotherContainer() {
+    func test(_ scope: ComponentScope, line: UInt = #line) {
+      let container1 = DependencyContainer()
+      container1.register(scope) { ServiceImp1() as Service }
+      
+      let container2 = DependencyContainer()
+      container1.collaborate(with: container2)
+      container2.collaborate(with: container1)
+      
+      try! container1.bootstrap()
+      try! container2.bootstrap()
+      
+      let service1 = try! container1.resolve() as Service
+      let service2 = try! container2.resolve() as Service
+      
+      XCTAssertTrue(service1 === service2, "\(scope) should be reused when first resolved from another container", line: line)
+    }
+    
+    test(.singleton)
+    test(.weakSingleton)
+    test(.eagerSingleton)
+  }
+  
+}
+
@@ -0,0 +1,261 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+import XCTest
+@testable import Dip
+
+private protocol Service {}
+private class ServiceImp1: Service {
+  let injected = Injected<ServiceImp2>()
+  let injectedWeak = InjectedWeak<ServiceImp2>()
+  let taggedInjected = Injected<ServiceImp2>(tag: "injectedTag")
+  let taggedInjectedWeak = InjectedWeak<ServiceImp2>(tag: "injectedTag")
+  let injectedNilTag = Injected<ServiceImp2>(tag: nil)
+}
+private class ServiceImp2: Service {}
+
+class ContextTests: XCTestCase {
+
+  let container = DependencyContainer()
+  
+  static var allTests = {
+    return [
+      ("testThatContextStoresCurrentlyResolvedType", testThatContextStoresCurrentlyResolvedType),
+      ("testThatContextStoresInjectedInType", testThatContextStoresInjectedInType),
+      ("testThatContextStoresTheTagPassedToResolve", testThatContextStoresTheTagPassedToResolve),
+      ("testThatContextStoresTheTagPassedToResolveWhenAutoInjecting", testThatContextStoresTheTagPassedToResolveWhenAutoInjecting),
+      ("testThatContextStoresTheTagPassedToResolveWhenAutoWiring", testThatContextStoresTheTagPassedToResolveWhenAutoWiring),
+      ("testThatContextDoesNotOverrideNilTagPassedToResolve", testThatContextDoesNotOverrideNilTagPassedToResolve),
+      ("testThatContextStoresNameOfAutoInjectedProperty", testThatContextStoresNameOfAutoInjectedProperty),
+      ("testThatItDoesNotSetInjectedInTypeWhenResolvingWithCollaboration", testThatItDoesNotSetInjectedInTypeWhenResolvingWithCollaboration),
+      ("testThatContextIsPreservedWhenResolvingWithCollaboration", testThatContextIsPreservedWhenResolvingWithCollaboration)
+    ]
+  }()
+  
+  override func setUp() {
+    container.reset()
+    container.register { ServiceImp2() }
+  }
+
+  func testThatContextStoresCurrentlyResolvedType() {
+    container.register { () -> Service in
+      XCTAssertTrue(self.container.context.resolvingType == Service.self)
+      let _ = try self.container.resolve() as ServiceImp1
+      return ServiceImp1() as Service
+      }.resolvingProperties { _,_  in
+        XCTAssertTrue(self.container.context.resolvingType == Service.self)
+        let _ = try self.container.resolve() as ServiceImp1
+    }
+    
+    container.register { () -> ServiceImp1 in
+      XCTAssertTrue(self.container.context.resolvingType == ServiceImp1.self)
+      return ServiceImp1()
+      }.resolvingProperties { _,_  in
+        XCTAssertTrue(self.container.context.resolvingType == ServiceImp1.self)
+    }
+    
+    let _ = try! container.resolve() as Service
+  }
+  
+  func testThatContextStoresInjectedInType() {
+    container.register { () -> Service in
+      XCTAssertNil(self.container.context.injectedInType)
+      let _ = try self.container.resolve() as ServiceImp1
+      return ServiceImp1() as Service
+      }.resolvingProperties { _,_  in
+        XCTAssertNil(self.container.context.injectedInType)
+        let _ = try self.container.resolve() as ServiceImp1
+    }
+    
+    container.register { () -> ServiceImp1 in
+      XCTAssertTrue(self.container.context.injectedInType == Service.self)
+      return ServiceImp1()
+      }.resolvingProperties { _,_  in
+        XCTAssertTrue(self.container.context.injectedInType == Service.self)
+    }
+    
+    let _ = try! container.resolve() as Service
+  }
+
+  func testThatContextStoresTheTagPassedToResolve() {
+    container.register { () -> Service in
+      XCTAssertNotNil(self.container.context.tag)
+      XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+      let _ = try self.container.resolve(tag: "otherTag") as ServiceImp1
+      return ServiceImp1() as Service
+      }.resolvingProperties { _,_  in
+        XCTAssertNotNil(self.container.context.tag)
+        XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+        let _ = try self.container.resolve(tag: "otherTag") as ServiceImp1
+    }
+    
+    container.register { () -> ServiceImp1 in
+      XCTAssertNotNil(self.container.context.tag)
+      XCTAssertTrue(DependencyContainer.Tag.String("otherTag") ~= self.container.context.tag!)
+      return ServiceImp1()
+      }.resolvingProperties { _,_  in
+        XCTAssertNotNil(self.container.context.tag)
+        XCTAssertTrue(DependencyContainer.Tag.String("otherTag") ~= self.container.context.tag!)
+    }
+    
+    let _ = try! container.resolve(tag: "tag") as Service
+  }
+  
+  func testThatContextStoresTheTagPassedToResolveWhenAutoInjecting() {
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp1() }
+    
+    container.register { () -> ServiceImp2 in
+      if self.container.context.injectedInProperty == "injectedNilTag" {
+        XCTAssertNil(self.container.context.tag)
+      }
+      else {
+        XCTAssertNotNil(self.container.context.tag)
+        XCTAssertTrue(DependencyContainer.Tag.String("injectedTag") ~= self.container.context.tag!)
+      }
+      return ServiceImp2()
+      }.resolvingProperties { _,_  in
+        if self.container.context.injectedInProperty == "injectedNilTag" {
+          XCTAssertNil(self.container.context.tag)
+        }
+        else {
+          XCTAssertNotNil(self.container.context.tag)
+          XCTAssertTrue(DependencyContainer.Tag.String("injectedTag") ~= self.container.context.tag!)
+        }
+    }
+    
+    container.register(tag: "tag") { () -> ServiceImp2 in
+      XCTAssertNotNil(self.container.context.tag)
+      XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+      return ServiceImp2()
+      }.resolvingProperties { _,_  in
+        XCTAssertNotNil(self.container.context.tag)
+        XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+    }
+    
+    let _ = try! container.resolve(tag: "tag") as Service
+  }
+
+  func testThatContextStoresTheTagPassedToResolveWhenAutoWiring() {
+    container.register { (_: ServiceImp1) -> Service in
+      return ServiceImp1() as Service
+      }.resolvingProperties { _,_  in
+    }
+    
+    container.register { () -> ServiceImp1 in
+      XCTAssertNotNil(self.container.context.tag)
+      XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+      return ServiceImp1()
+      }.resolvingProperties { _,_  in
+        XCTAssertNotNil(self.container.context.tag)
+        XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+    }
+    
+    let _ = try! container.resolve(tag: "tag") as Service
+  }
+
+  func testThatContextDoesNotOverrideNilTagPassedToResolve() {
+    container.register { () -> Service in
+      XCTAssertNotNil(self.container.context.tag)
+      XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+      let _ = try self.container.resolve() as ServiceImp1
+      return ServiceImp1() as Service
+      }.resolvingProperties { _,_  in
+        XCTAssertNotNil(self.container.context.tag)
+        XCTAssertTrue(DependencyContainer.Tag.String("tag") ~= self.container.context.tag!)
+        let _ = try self.container.resolve() as ServiceImp1
+    }
+    
+    container.register { () -> ServiceImp1 in
+      XCTAssertNil(self.container.context.tag)
+      return ServiceImp1()
+      }.resolvingProperties { _,_  in
+        XCTAssertNil(self.container.context.tag)
+    }
+    
+    let _ = try! container.resolve(tag: "tag") as Service
+  }
+  
+  func testThatContextStoresNameOfAutoInjectedProperty() {
+    container.register { ServiceImp1() as Service }
+    container.register { ServiceImp1() }
+    
+    let names = ["injected", "injectedWeak", "taggedInjected", "taggedInjectedWeak", "injectedNilTag"]
+    
+    container.register { () -> ServiceImp2 in
+      XCTAssertNotNil(self.container.context.injectedInProperty)
+      XCTAssertTrue(names.contains(self.container.context.injectedInProperty!))
+      return ServiceImp2()
+      }.resolvingProperties { _,_  in
+        XCTAssertNotNil(self.container.context.injectedInProperty)
+        XCTAssertTrue(names.contains(self.container.context.injectedInProperty!))
+    }
+    
+    let _ = try! container.resolve() as Service
+  }
+  
+  func testThatItDoesNotSetInjectedInTypeWhenResolvingWithCollaboration() {
+    let collaborator = DependencyContainer()
+    
+    collaborator.register { () -> ServiceImp1 in
+      unowned let collaborator = collaborator
+      XCTAssertNil(collaborator.context.injectedInType)
+      return ServiceImp1()
+      }.resolvingProperties { collaborator, _ in
+        XCTAssertNil(collaborator.context.injectedInType)
+    }
+    
+    container.collaborate(with: collaborator)
+    collaborator.collaborate(with: container)
+    
+    let _ = try! container.resolve() as ServiceImp1
+  }
+  
+  func testThatContextIsPreservedWhenResolvingWithCollaboration() {
+    let collaborator = DependencyContainer()
+    
+    container.register { () -> Service in
+      XCTAssertTrue(self.container.context.resolvingType == Service.self)
+      let _ = try self.container.resolve() as ServiceImp1
+      return ServiceImp1() as Service
+      }.resolvingProperties { _,_  in
+        XCTAssertTrue(self.container.context.resolvingType == Service.self)
+        let _ = try self.container.resolve() as ServiceImp1
+    }
+    
+    collaborator.register { () -> ServiceImp1 in
+      XCTAssertTrue(collaborator.context.resolvingType == ServiceImp1.self)
+      return ServiceImp1()
+      }.resolvingProperties { _,_  in
+        XCTAssertTrue(collaborator.context.resolvingType == ServiceImp1.self)
+    }
+    
+    container.collaborate(with: collaborator)
+    collaborator.collaborate(with: container)
+    let _ = try! container.resolve() as Service
+
+    collaborator.reset()
+  }
+  
+}
@@ -36,46 +36,45 @@ class DefinitionTests: XCTestCase {
  let tag1 = DependencyContainer.Tag.String("tag1")
  let tag2 = DependencyContainer.Tag.String("tag2")
  
-  #if os(Linux)
-  var allTests: [(String, () throws -> Void)] {
+  static var allTests = {
    return [
      ("testThatDefinitionKeyIsEqualBy_Type_Factory_Tag", testThatDefinitionKeyIsEqualBy_Type_Factory_Tag),
      ("testThatDefinitionKeysWithDifferentTypesAreNotEqual", testThatDefinitionKeysWithDifferentTypesAreNotEqual),
      ("testThatDefinitionKeysWithDifferentFactoriesAreNotEqual", testThatDefinitionKeysWithDifferentFactoriesAreNotEqual),
      ("testThatDefinitionKeysWithDifferentTagsAreNotEqual", testThatDefinitionKeysWithDifferentTagsAreNotEqual),
      ("testThatResolveDependenciesCallsResolveDependenciesBlock", testThatResolveDependenciesCallsResolveDependenciesBlock),
-      ("testThatResolveDependenciesBlockIsNotCalledWhenPassedWrongInstance", testThatResolveDependenciesBlockIsNotCalledWhenPassedWrongInstance)
+      ("testThatResolveDependenciesBlockIsNotCalledWhenPassedWrongInstance", testThatResolveDependenciesBlockIsNotCalledWhenPassedWrongInstance),
+      ("testThatItRegisteresOptionalTypesAsForwardedTypes", testThatItRegisteresOptionalTypesAsForwardedTypes)
    ]
-  }
-  #endif
+  }()

  func testThatDefinitionKeyIsEqualBy_Type_Factory_Tag() {
-    let equalKey1 = DefinitionKey(protocolType: Service.self, factoryType: F1.self, associatedTag: tag1)
-    let equalKey2 = DefinitionKey(protocolType: Service.self, factoryType: F1.self, associatedTag: tag1)
+    let equalKey1 = DefinitionKey(type: Service.self, typeOfArguments: F1.self, tag: tag1)
+    let equalKey2 = DefinitionKey(type: Service.self, typeOfArguments: F1.self, tag: tag1)
    
    XCTAssertEqual(equalKey1, equalKey2)
    XCTAssertEqual(equalKey1.hashValue, equalKey2.hashValue)
  }
  
  func testThatDefinitionKeysWithDifferentTypesAreNotEqual() {
-    let keyWithDifferentType1 = DefinitionKey(protocolType: Service.self, factoryType: F1.self, associatedTag: nil)
-    let keyWithDifferentType2 = DefinitionKey(protocolType: AnyObject.self, factoryType: F1.self, associatedTag: nil)
+    let keyWithDifferentType1 = DefinitionKey(type: Service.self, typeOfArguments: F1.self, tag: nil)
+    let keyWithDifferentType2 = DefinitionKey(type: AnyObject.self, typeOfArguments: F1.self, tag: nil)
    
    XCTAssertNotEqual(keyWithDifferentType1, keyWithDifferentType2)
    XCTAssertNotEqual(keyWithDifferentType1.hashValue, keyWithDifferentType2.hashValue)
  }
  
  func testThatDefinitionKeysWithDifferentFactoriesAreNotEqual() {
-    let keyWithDifferentFactory1 = DefinitionKey(protocolType: Service.self, factoryType: F1.self, associatedTag: nil)
-    let keyWithDifferentFactory2 = DefinitionKey(protocolType: Service.self, factoryType: F2.self, associatedTag: nil)
+    let keyWithDifferentFactory1 = DefinitionKey(type: Service.self, typeOfArguments: F1.self, tag: nil)
+    let keyWithDifferentFactory2 = DefinitionKey(type: Service.self, typeOfArguments: F2.self, tag: nil)
    
    XCTAssertNotEqual(keyWithDifferentFactory1, keyWithDifferentFactory2)
    XCTAssertNotEqual(keyWithDifferentFactory1.hashValue, keyWithDifferentFactory2.hashValue)
  }
  
  func testThatDefinitionKeysWithDifferentTagsAreNotEqual() {
-    let keyWithDifferentTag1 = DefinitionKey(protocolType: Service.self, factoryType: F1.self, associatedTag: tag1)
-    let keyWithDifferentTag2 = DefinitionKey(protocolType: Service.self, factoryType: F1.self, associatedTag: tag2)
+    let keyWithDifferentTag1 = DefinitionKey(type: Service.self, typeOfArguments: F1.self, tag: tag1)
+    let keyWithDifferentTag2 = DefinitionKey(type: Service.self, typeOfArguments: F1.self, tag: tag2)
    
    XCTAssertNotEqual(keyWithDifferentTag1, keyWithDifferentTag2)
    XCTAssertNotEqual(keyWithDifferentTag1.hashValue, keyWithDifferentTag2.hashValue)
@@ -85,12 +84,13 @@ class DefinitionTests: XCTestCase {
    var blockCalled = false
    
    //given
-    let def = DefinitionOf<Service, () -> Service>(scope: .Prototype) { ServiceImp() as Service }.resolveDependencies { container, service in
-      blockCalled = true
+    let def = Definition<Service, ()>(scope: .unique) { ServiceImp() as Service }
+      .resolvingProperties { container, service in
+        blockCalled = true
    }
    
    //when
-    try! def.resolveDependenciesOf(ServiceImp(), withContainer: DependencyContainer())
+    try! def.resolveProperties(of: ServiceImp(), container: DependencyContainer())
    
    //then
    XCTAssertTrue(blockCalled)
@@ -100,15 +100,24 @@ class DefinitionTests: XCTestCase {
    var blockCalled = false
    
    //given
-    let def = DefinitionOf<Service, () -> Service>(scope: .Prototype) { ServiceImp() as Service }.resolveDependencies { container, service in
-      blockCalled = true
+    let def = Definition<Service, ()>(scope: .unique) { ServiceImp() as Service }
+      .resolvingProperties { container, service in
+        blockCalled = true
    }
    
    //when
-    try! def.resolveDependenciesOf(String(), withContainer: DependencyContainer())
+    try! def.resolveProperties(of: String(), container: DependencyContainer())
    
    //then
    XCTAssertFalse(blockCalled)
  }
+  
+  func testThatItRegisteresOptionalTypesAsForwardedTypes() {
+    let def = Definition<Service, ()>(scope: .unique) { ServiceImp() as Service }
+    
+    XCTAssertTrue(def.implementingTypes.contains(where: { $0 == Service?.self }))
+    XCTAssertTrue(def.implementingTypes.contains(where: { $0 == Service!.self }))
+  }
+  
 }

@@ -0,0 +1,833 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+import XCTest
+@testable import Dip
+
+private protocol Service: class { }
+private class ServiceImp1: Service { }
+private class ServiceImp2: Service { }
+
+private protocol Server: class {
+  weak var client: Client! { get }
+}
+private protocol Client: class {
+  var server: Server! { get }
+}
+
+class ResolvableService: Service, Resolvable {
+  var didResolveDependenciesCalled = false
+  
+  func didResolveDependencies() {
+    XCTAssertFalse(didResolveDependenciesCalled, "didResolveDependencies should be called only once per instance")
+    didResolveDependenciesCalled = true
+  }
+}
+
+class DipTests: XCTestCase {
+
+  let container = DependencyContainer()
+
+  static var allTests = {
+    return [
+      ("testThatCreatingContainerWithConfigBlockDoesNotCreateRetainCycle", testThatCreatingContainerWithConfigBlockDoesNotCreateRetainCycle),
+      ("testThatItResolvesInstanceRegisteredWithoutTag", testThatItResolvesInstanceRegisteredWithoutTag),
+      ("testThatItResolvesInstanceRegisteredWithTag", testThatItResolvesInstanceRegisteredWithTag),
+      ("testThatItResolvesDifferentInstancesRegisteredForDifferentTags", testThatItResolvesDifferentInstancesRegisteredForDifferentTags),
+      ("testThatNewRegistrationOverridesPreviousRegistration", testThatNewRegistrationOverridesPreviousRegistration),
+      ("testThatItCallsResolveDependenciesOnDefinition", testThatItCallsResolveDependenciesOnDefinition),
+      ("testThatItThrowsErrorIfCanNotFindDefinitionForType", testThatItThrowsErrorIfCanNotFindDefinitionForType),
+      ("testThatItThrowsErrorIfCanNotFindDefinitionForTag", testThatItThrowsErrorIfCanNotFindDefinitionForTag),
+      ("testThatItThrowsErrorIfCanNotFindDefinitionForFactoryWithArguments", testThatItThrowsErrorIfCanNotFindDefinitionForFactoryWithArguments),
+      ("testThatItThrowsErrorIfConstructorThrows", testThatItThrowsErrorIfConstructorThrows),
+      ("testThatItThrowsErrorIfFailsToResolveDependency", testThatItThrowsErrorIfFailsToResolveDependency),
+      ("testThatItCallsDidResolveDependenciesOnResolvableIntance", testThatItCallsDidResolveDependenciesOnResolvableIntance),
+      ("testThatItCallsDidResolveDependenciesInReverseOrder", testThatItCallsDidResolveDependenciesInReverseOrder),
+      ("testItCallsResolveDependenciesOnResolableInstance", testItCallsResolveDependenciesOnResolableInstance),
+      ("testThatItResolvesCircularDependencies", testThatItResolvesCircularDependencies),
+      ("testThatItCanResolveUsingContainersCollaboration", testThatItCanResolveUsingContainersCollaboration),
+      ("testThatCollaboratingWithSelfIsIgnored", testThatCollaboratingWithSelfIsIgnored),
+      ("testThatCollaboratingContainersAreWeakReferences", testThatCollaboratingContainersAreWeakReferences),
+      ("testThatCollaboratingContainersReuseInstancesResolvedByAnotherContainer", testThatCollaboratingContainersReuseInstancesResolvedByAnotherContainer),
+    ]
+  }()
+
+  override func setUp() {
+    container.reset()
+  }
+  
+  func testThatCreatingContainerWithConfigBlockDoesNotCreateRetainCycle() {
+    var container: DependencyContainer! = DependencyContainer() { container in
+      //compiler crashes if you try to capture container in capture list
+      //so instead we capture it in a variable
+      unowned let container = container
+      
+      container.register { ServiceImp1() }
+      container.register { (_: ServiceImp1)->Service in
+        //referencing container in factory
+        let _ = container
+        return ServiceImp1() as Service
+        }.resolvingProperties { container, _ in
+          //when container is passed as argument there will be no retain cycle
+          let _ = container
+      }
+    }
+    
+    let _ = try! container.resolve() as Service
+
+    weak var weakContainer = container
+    container = nil
+    
+    XCTAssertNil(weakContainer)
+  }
+
+  func testThatItResolvesInstanceRegisteredWithoutTag() {
+    //given
+    container.register { ServiceImp1() as Service }
+    
+    //when
+    let serviceInstance = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(serviceInstance is ServiceImp1)
+    
+    //and when
+    let anyService = try! container.resolve(Service.self)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
+
+    //and when
+    let optService = try! container.resolve((Service?).self)
+    
+    //then
+    XCTAssertTrue(optService is ServiceImp1)
+    
+    //and when
+    let impService = try! container.resolve((Service!).self)
+    
+    //then
+    XCTAssertTrue(impService is ServiceImp1)
+  }
+  
+  func testThatItResolvesInstanceRegisteredWithTag() {
+    //given
+    container.register(tag: "service") { ServiceImp1() as Service }
+    
+    //when
+    let serviceInstance = try! container.resolve(tag: "service") as Service
+    
+    //then
+    XCTAssertTrue(serviceInstance is ServiceImp1)
+
+    //and when
+    let anyService = try! container.resolve(Service.self, tag: "service")
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
+    
+    //and when
+    let optService = try! container.resolve((Service?).self, tag: "service")
+    
+    //then
+    XCTAssertTrue(optService is ServiceImp1)
+    
+    //and when
+    let impService = try! container.resolve((Service!).self, tag: "service")
+    
+    //then
+    XCTAssertTrue(impService is ServiceImp1)
+  }
+  
+  func testThatItResolvesDifferentInstancesRegisteredForDifferentTags() {
+    //given
+    container.register(tag: "service1") { ServiceImp1() as Service }
+    container.register(tag: "service2") { ServiceImp2() as Service }
+    
+    //when
+    let service1Instance = try! container.resolve(tag: "service1") as Service
+    let service2Instance = try! container.resolve(tag: "service2") as Service
+    
+    //then
+    XCTAssertTrue(service1Instance is ServiceImp1)
+    XCTAssertTrue(service2Instance is ServiceImp2)
+    
+    //and when
+    let anyService1 = try! container.resolve(Service.self, tag: "service1")
+    let anyService2 = try! container.resolve(Service.self, tag: "service2")
+    
+    //then
+    XCTAssertTrue(anyService1 is ServiceImp1)
+    XCTAssertTrue(anyService2 is ServiceImp2)
+
+    //and when
+    let optService1 = try! container.resolve((Service?).self, tag: "service1")
+    let optService2 = try! container.resolve((Service?).self, tag: "service2")
+    
+    //then
+    XCTAssertTrue(optService1 is ServiceImp1)
+    XCTAssertTrue(optService2 is ServiceImp2)
+  
+    //and when
+    let impService1 = try! container.resolve((Service!).self, tag: "service1")
+    let impService2 = try! container.resolve((Service!).self, tag: "service2")
+    
+    //then
+    XCTAssertTrue(impService1 is ServiceImp1)
+    XCTAssertTrue(impService2 is ServiceImp2)
+  }
+  
+  func testThatNewRegistrationOverridesPreviousRegistration() {
+    //given
+    container.register { ServiceImp1() as Service }
+    let service1 = try! container.resolve() as Service
+    
+    //when
+    container.register { ServiceImp2() as Service }
+    let service2 = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(service1 is ServiceImp1)
+    XCTAssertTrue(service2 is ServiceImp2)
+  }
+  
+  func testThatItCallsResolveDependenciesOnDefinition() {
+    //given
+    var resolveDependenciesCalled = false
+    container.register { ServiceImp1() as Service }.resolvingProperties { (c, s) in
+      resolveDependenciesCalled = true
+    }
+    
+    //when
+    let _ = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(resolveDependenciesCalled)
+    resolveDependenciesCalled = false
+    
+    //and when
+    let _ = try! container.resolve(Service.self)
+    
+    //then
+    XCTAssertTrue(resolveDependenciesCalled)
+
+    resolveDependenciesCalled = false
+    
+    //and when
+    let _ = try! container.resolve((Service?).self)
+    
+    //then
+    XCTAssertTrue(resolveDependenciesCalled)
+
+    resolveDependenciesCalled = false
+    
+    //and when
+    let _ = try! container.resolve((Service!).self)
+    
+    //then
+    XCTAssertTrue(resolveDependenciesCalled)
+  }
+  
+  func testThatItThrowsErrorIfCanNotFindDefinitionForType() {
+    //given
+    container.register { ServiceImp1() as ServiceImp1 }
+    
+    //when
+    AssertThrows(expression: try container.resolve() as Service) { error in
+      guard case let DipError.definitionNotFound(key) = error else { return false }
+      
+      //then
+      let expectedKey = DefinitionKey(type: Service.self, typeOfArguments: Void.self, tag: nil)
+      XCTAssertEqual(key, expectedKey)
+
+      return true
+    }
+
+    //and when
+    AssertThrows(expression: try container.resolve(Service.self)) { error in
+      guard case let DipError.definitionNotFound(key) = error else { return false }
+      
+      //then
+      let expectedKey = DefinitionKey(type: Service.self, typeOfArguments: Void.self, tag: nil)
+      XCTAssertEqual(key, expectedKey)
+      
+      return true
+    }
+  }
+  
+  func testThatItThrowsErrorIfCanNotFindDefinitionForTag() {
+    //given
+    container.register(tag: "some tag") { ServiceImp1() as Service }
+    
+    //when
+    AssertThrows(expression: try container.resolve(tag: "other tag") as Service) { error in
+      guard case let DipError.definitionNotFound(key) = error else { return false }
+      
+      //then
+      let expectedKey = DefinitionKey(type: Service.self, typeOfArguments: Void.self, tag: "other tag")
+      XCTAssertEqual(key, expectedKey)
+      
+      return true
+    }
+
+    //and when
+    AssertThrows(expression: try container.resolve(Service.self, tag: "other tag")) { error in
+      guard case let DipError.definitionNotFound(key) = error else { return false }
+      
+      //then
+      let expectedKey = DefinitionKey(type: Service.self, typeOfArguments: Void.self, tag: "other tag")
+      XCTAssertEqual(key, expectedKey)
+      
+      return true
+    }
+  }
+  
+  func testThatItThrowsErrorIfCanNotFindDefinitionForFactoryWithArguments() {
+    //given
+    container.register { ServiceImp1() as Service }
+    
+    //when
+    AssertThrows(expression: try container.resolve(arguments: "some string") as Service) { error in
+      guard case let DipError.definitionNotFound(key) = error else { return false }
+      
+      //then
+      let expectedKey = DefinitionKey(type: Service.self, typeOfArguments: String.self, tag: nil)
+      XCTAssertEqual(key, expectedKey)
+
+      return true
+    }
+
+    //and when
+    AssertThrows(expression: try container.resolve(Service.self, arguments: "some string")) { error in
+      guard case let DipError.definitionNotFound(key) = error else { return false }
+      
+      //then
+      let expectedKey = DefinitionKey(type: Service.self, typeOfArguments: String.self, tag: nil)
+      XCTAssertEqual(key, expectedKey)
+      
+      return true
+    }
+  }
+  
+  func testThatItThrowsErrorIfConstructorThrows() {
+    //given
+    let failedKey = DefinitionKey(type: Any.self, typeOfArguments: Any.self)
+    let expectedError = DipError.definitionNotFound(key: failedKey)
+    container.register { () throws -> Service in throw expectedError }
+    
+    //when
+    AssertThrows(expression: try container.resolve() as Service) { error in
+      switch error {
+      case let DipError.definitionNotFound(key) where key == failedKey: return true
+      default: return false
+      }
+    }
+    
+    //and when
+    AssertThrows(expression: try container.resolve(Service.self)) { error in
+      switch error {
+      case let DipError.definitionNotFound(key) where key == failedKey: return true
+      default: return false
+      }
+    }
+  }
+  
+  func testThatItThrowsErrorIfFailsToResolveDependency() {
+    //given
+    let failedKey = DefinitionKey(type: Any.self, typeOfArguments: Any.self)
+    let expectedError = DipError.definitionNotFound(key: failedKey)
+    container.register { ServiceImp1() as Service }
+      .resolvingProperties { container, service in
+        //simulate throwing error when resolving dependency
+        throw expectedError
+    }
+    
+    //when
+    AssertThrows(expression: try container.resolve() as Service) { error in
+      switch error {
+      case let DipError.definitionNotFound(key) where key == failedKey: return true
+      default: return false
+      }
+    }
+    
+    //and when
+    AssertThrows(expression: try container.resolve(Service.self)) { error in
+      switch error {
+      case let DipError.definitionNotFound(key) where key == failedKey: return true
+      default: return false
+      }
+    }
+  }
+
+  func testThatItCallsDidResolveDependenciesOnResolvableIntance() {
+    //given
+    container.register { ResolvableService() as Service }
+      .resolvingProperties { _, service in
+        XCTAssertFalse((service as! ResolvableService).didResolveDependenciesCalled, "didResolveDependencies should not be called yet")
+        return
+    }
+
+    container.register(tag: "graph") { ResolvableService() as Service }
+      .resolvingProperties { _, service in
+        XCTAssertFalse((service as! ResolvableService).didResolveDependenciesCalled, "didResolveDependencies should not be called yet")
+        return
+    }
+
+    container.register(.singleton, tag: "singleton") { ResolvableService() as Service }
+      .resolvingProperties { _, service in
+        XCTAssertFalse((service as! ResolvableService).didResolveDependenciesCalled, "didResolveDependencies should not be called yet")
+        return
+    }
+
+    //when
+    let service = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue((service as! ResolvableService).didResolveDependenciesCalled)
+
+    //and when
+    let graphService = try! container.resolve(tag: "graph") as Service
+    
+    //then
+    XCTAssertTrue((graphService as! ResolvableService).didResolveDependenciesCalled)
+    
+    //and when
+    let singletonService = try! container.resolve(tag: "singleton") as Service
+    let _ = try! container.resolve(tag: "singleton") as Service
+    
+    //then
+    XCTAssertTrue((singletonService as! ResolvableService).didResolveDependenciesCalled)
+  }
+  
+  func testThatItCallsDidResolveDependenciesInReverseOrder() {
+    
+    class ResolvableService: Service, Resolvable {
+      static var resolved: [Service] = []
+      
+      func didResolveDependencies() {
+        ResolvableService.resolved.append(self)
+      }
+    }
+    
+    //given
+    var resolveDependenciesCalled = false
+    var service2: Service!
+    container.register { ResolvableService() as Service }
+      .resolvingProperties { _, service in
+        if !resolveDependenciesCalled {
+          resolveDependenciesCalled = true
+          service2 = try self.container.resolve() as Service
+        }
+        return
+    }
+
+    //when
+    let service1 = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(ResolvableService.resolved.first === service2)
+    XCTAssertTrue(ResolvableService.resolved.last === service1)
+  }
+  
+  func testItCallsResolveDependenciesOnResolableInstance() {
+    
+    class Class: Resolvable {
+      var resolveDependenciesCalled = false
+      
+      func resolveDependencies(_ container: DependencyContainer) {
+        resolveDependenciesCalled = true
+      }
+    }
+    
+    class SubClass: Class {
+      override func resolveDependencies(_ container: DependencyContainer) {
+        super.resolveDependencies(container)
+      }
+    }
+    
+    container.register { Class() }
+      .resolvingProperties { _, instance in
+        XCTAssertTrue(instance.resolveDependenciesCalled)
+    }
+    
+    container.register { SubClass() }
+      .resolvingProperties { _, instance in
+        XCTAssertTrue(instance.resolveDependenciesCalled)
+    }
+    
+    let _ = try! container.resolve() as Class
+    let _ = try! container.resolve() as SubClass
+  }
+  
+  func testThatItResolvesCircularDependencies() {
+    
+    class ResolvableServer: Server, Resolvable {
+      weak var client: Client!
+      weak var secondClient: Client!
+      
+      init(client: Client) {
+        self.client = client
+      }
+      
+      var didResolveDependenciesCalled = false
+      
+      func didResolveDependencies() {
+        XCTAssertFalse(didResolveDependenciesCalled, "didResolveDependencies should be called only once per instance")
+        didResolveDependenciesCalled = true
+
+        XCTAssertNotNil(self.client)
+        XCTAssertNotNil(self.secondClient)
+        XCTAssertNotNil(self.client?.server)
+        XCTAssertNotNil(self.secondClient)
+        XCTAssertNotNil(self.secondClient?.server)
+      }
+      
+    }
+    
+    class ResolvableClient: Client, Resolvable {
+      var server: Server!
+      var secondServer: Server!
+      
+      var didResolveDependenciesCalled = false
+      
+      func didResolveDependencies() {
+        XCTAssertFalse(didResolveDependenciesCalled, "didResolveDependencies should be called only once per instance")
+        didResolveDependenciesCalled = true
+
+        XCTAssertNotNil(self.server)
+        XCTAssertNotNil(self.secondServer)
+        XCTAssertNotNil(self.server?.client)
+        XCTAssertNotNil(self.secondServer?.client)
+      }
+      
+    }
+
+    //given
+    container.register { try ResolvableServer(client: self.container.resolve()) as Server }
+      .resolvingProperties { (container: DependencyContainer, server: Server) in
+        let server = server as! ResolvableServer
+        server.secondClient = try container.resolve() as Client
+    }
+    
+    container.register { ResolvableClient() as Client }
+      .resolvingProperties { (container: DependencyContainer, client: Client) in
+        let client = client as! ResolvableClient
+        client.server = try container.resolve() as Server
+        client.secondServer = try container.resolve() as Server
+    }
+
+    //when
+    let client = (try! container.resolve() as Client) as! ResolvableClient
+    let server = client.server as! ResolvableServer
+    let secondServer = client.secondServer as! ResolvableServer
+    let secondClient = server.secondClient as! ResolvableClient
+    
+    //then
+    XCTAssertTrue(client === server.client)
+    XCTAssertTrue(client === server.secondClient)
+    XCTAssertTrue(client === secondServer.client)
+    XCTAssertTrue(client === secondServer.secondClient)
+    XCTAssertTrue(client === secondClient)
+    XCTAssertTrue(server === secondServer)
+    
+    XCTAssertTrue(client.didResolveDependenciesCalled)
+    XCTAssertTrue(server.didResolveDependenciesCalled)
+  }
+  
+  func testThatItValidatesConfiguration() {
+    //given
+    var createdService1 = false
+    var createdService2 = false
+    var createdService3 = false
+    var createdService = false
+    
+    container.register { ServiceImp1() }
+      .resolvingProperties { container, _ in
+        if container.context.resolvingType == ServiceImp1.self {
+          createdService1 = true
+        }
+        if container.context.resolvingType == Service.self {
+          createdService = true
+        }
+      }.implements(Service.self)
+    
+    container.register(tag: "tag") { ServiceImp2() as Service }
+      .resolvingProperties { _,_  in
+        createdService2 = true
+    }
+    
+    container.register { (arg: String) in ServiceImp1() }
+      .resolvingProperties { _,_  in
+        createdService3 = true
+    }
+    
+    //then
+    AssertNoThrow(expression: try container.validate("arg"))
+    XCTAssertTrue(createdService1)
+    XCTAssertTrue(createdService2)
+    XCTAssertTrue(createdService3)
+    XCTAssertTrue(createdService)
+  }
+  
+  func testThatItPicksRuntimeArgumentsWhenValidatingConfiguration() {
+    //given
+    let expectedIntArgument = 1
+    let expectedStringArgument = "a"
+    container.register { (a: Int) -> Service in
+      XCTAssertEqual(a, expectedIntArgument)
+      return ServiceImp1() as Service
+    }
+    
+    container.register { (a: Int, b: String) -> Service in
+      XCTAssertEqual(a, expectedIntArgument)
+      XCTAssertEqual(b, expectedStringArgument)
+      return ServiceImp1() as Service
+    }
+    
+    //then
+    AssertNoThrow(expression:
+      try container.validate(
+        "1",
+        expectedIntArgument,
+        "x",
+        (expectedStringArgument, expectedIntArgument),
+        (expectedIntArgument, expectedStringArgument)
+      )
+    )
+  }
+  
+  func testThatItFailsValidationIfNoMatchingArgumentsFound() {
+    //given
+    container.register { (a: Int) -> Service in ServiceImp1() as Service }
+    
+    //then
+    AssertThrows(expression: try container.validate()) { error in error is DipError }
+    AssertThrows(expression: try container.validate("1")) { error in error is DipError }
+  }
+  
+  func testThatItFailsValidationOnlyForDipErrors() {
+    //given
+    enum SomeError: Error { case error }
+    
+    container.register { () -> Service in
+      throw SomeError.error
+    }
+    
+    //then
+    AssertNoThrow(expression: try container.validate())
+    
+    //given
+    let key = DefinitionKey(type: Service.self, typeOfArguments: Void.self, tag: nil)
+    container.register { () -> Service in
+      throw DipError.definitionNotFound(key: key)
+    }
+    
+    //then
+    AssertThrows(expression: try container.validate()) { error in
+      if case let DipError.definitionNotFound(_key) = error, _key == key { return true }
+      else { return false }
+    }
+  }
+  
+}
+
+extension DipTests {
+
+  func testThatItCanResolveUsingContainersCollaboration() {
+    //given
+    let collaborator = DependencyContainer()
+    collaborator.register { ResolvableService() as Service }
+    container.register { "something" }
+
+    //when
+    container.collaborate(with: collaborator)
+    
+    //then
+    AssertNoThrow(expression: try container.resolve() as Service)
+    AssertNoThrow(expression: try container.resolve(Service.self))
+    AssertNoThrow(expression: try collaborator.resolve() as String)
+    AssertNoThrow(expression: try collaborator.resolve(String.self))
+  }
+  
+  func testThatCollaboratingWithSelfIsIgnored() {
+    let collaborator = DependencyContainer()
+    collaborator.collaborate(with: collaborator)
+    XCTAssertTrue(collaborator._collaborators.isEmpty, "Container should not collaborate with itself")
+  }
+  
+  func testThatCollaboratingContainersAreWeakReferences() {
+    //given
+    var collaborator: DependencyContainer? = DependencyContainer()
+    weak var weakCollaborator = collaborator
+    
+    //when
+    container.collaborate(with: collaborator!)
+    collaborator = nil
+    
+    //then
+    XCTAssertNil(weakCollaborator)
+  }
+  
+  func testThatCollaboratingContainersReuseInstancesResolvedByAnotherContainer() {
+    //given
+    class ServerImp: Server {
+      weak var client: Client!
+      init(client: Client) { self.client = client }
+    }
+    
+    class ClientImp: Client {
+      var server: Server!
+      var anotherServer: Server!
+    }
+    
+    let serverContainer = DependencyContainer()
+    serverContainer.register { ServerImp(client: $0) as Server }
+
+    let clientContainer = DependencyContainer()
+    clientContainer.register { ClientImp() as Client }
+      .resolvingProperties { container, client in
+        let client = client as! ClientImp
+        client.server = try container.resolve() as Server
+        client.anotherServer = try container.resolve() as Server
+    }
+
+    //when
+    serverContainer.collaborate(with: clientContainer)
+    clientContainer.collaborate(with: serverContainer)
+    var client = try? clientContainer.resolve() as Client
+    
+    //then
+    XCTAssertNotNil(client)
+    XCTAssertTrue(client === client?.server?.client)
+    XCTAssertTrue(client === (client as? ClientImp)?.anotherServer?.client)
+    XCTAssertTrue(client?.server === (client as? ClientImp)?.anotherServer)
+    
+    client = try? serverContainer.resolve() as Client
+    
+    //then
+    XCTAssertNotNil(client)
+    XCTAssertTrue(client === client?.server?.client)
+    XCTAssertTrue(client === (client as? ClientImp)?.anotherServer?.client)
+    XCTAssertTrue(client?.server === (client as? ClientImp)?.anotherServer)
+  }
+  
+  func testThatCollaborationReferencesAreRecursivelyUpdate() {
+    let container = DependencyContainer()
+    container.register(.singleton){ ResolvableService() as Service }
+    
+    //when
+    let collaborator1 = DependencyContainer()
+    let collaborator2 = DependencyContainer()
+    let collaborator3 = DependencyContainer()
+    let collaborator4 = DependencyContainer()
+    
+    collaborator1.collaborate(with: container)
+    XCTAssertTrue(collaborator1.resolvedInstances.sharedSingletonsBox === container.resolvedInstances.sharedSingletonsBox)
+
+    collaborator2.collaborate(with: container)
+    XCTAssertTrue(collaborator2.resolvedInstances.sharedSingletonsBox === container.resolvedInstances.sharedSingletonsBox)
+
+    collaborator3.collaborate(with: collaborator1)
+    XCTAssertTrue(collaborator3.resolvedInstances.sharedSingletonsBox === container.resolvedInstances.sharedSingletonsBox)
+
+    collaborator4.collaborate(with: collaborator2)
+    XCTAssertTrue(collaborator4.resolvedInstances.sharedSingletonsBox === container.resolvedInstances.sharedSingletonsBox)
+    
+    let service1 = try! collaborator1.resolve() as Service
+    let service2 = try! collaborator2.resolve() as Service
+    let service3 = try! collaborator3.resolve() as Service
+    let service4 = try! collaborator4.resolve() as Service
+    let serviceRoot = try! container.resolve() as Service
+    
+    XCTAssertTrue(service1 === service2)
+    XCTAssertTrue(service1 === service3)
+    XCTAssertTrue(service1 === service4)
+    
+    XCTAssertTrue(service1 === serviceRoot)
+    XCTAssertTrue(service2 === serviceRoot)
+    XCTAssertTrue(service3 === serviceRoot)
+    XCTAssertTrue(service4 === serviceRoot)
+  }
+
+  class RootService {}
+  class ServiceClient {
+    let name: String
+    let service: RootService
+    init(name: String, service: RootService) {
+      self.name = name
+      self.service = service
+    }
+  }
+
+  func testThatContainersShareTheirSingletonsOnlyWithCollaborators() {
+    let container = DependencyContainer()
+    container.register(.singleton) { RootService() }
+    
+    let collaborator1 = DependencyContainer()
+    collaborator1.register(.singleton) {
+      ServiceClient(name: "1", service: $0)
+    }
+    
+    let collaborator2 = DependencyContainer()
+    collaborator2.register(.singleton) {
+      ServiceClient(name: "2", service: $0)
+    }
+    
+    collaborator1.collaborate(with: container)
+    collaborator2.collaborate(with: container)
+    
+    let client2 = try! collaborator2.resolve() as ServiceClient
+    let client1 = try! collaborator1.resolve() as ServiceClient
+    
+    XCTAssertEqual(client1.name, "1")
+    XCTAssertEqual(client2.name, "2")
+    XCTAssertTrue(client1.service === client2.service)
+  }
+
+  func testThatContainerAutowireBeforeCollaboration() {
+    let container = DependencyContainer()
+    container.register(.singleton) { RootService() }
+    
+    let collaborator1 = DependencyContainer()
+    collaborator1.register(.singleton) {
+      ServiceClient(name: "1", service: $0)
+    }
+    
+    let collaborator2 = DependencyContainer()
+    collaborator2.register(.singleton) {
+      ServiceClient(name: "2", service: $0)
+    }
+    
+    collaborator1.collaborate(with: container, collaborator2)
+    collaborator2.collaborate(with: container, collaborator1)
+    
+    let client2 = try! collaborator2.resolve() as ServiceClient
+    let client1 = try! collaborator1.resolve() as ServiceClient
+    
+    XCTAssertEqual(client1.name, "1")
+    XCTAssertEqual(client2.name, "2")
+    XCTAssertTrue(client1.service === client2.service)
+  }
+
+}
@@ -51,8 +51,7 @@ class RuntimeArgumentsTests: XCTestCase {
  
  let container = DependencyContainer()
 
-  #if os(Linux)
-  var allTests: [(String, () throws -> Void)] {
+  static var allTests = {
    return [
      ("testThatItResolvesInstanceWithOneArgument", testThatItResolvesInstanceWithOneArgument),
      ("testThatItResolvesInstanceWithTwoArguments", testThatItResolvesInstanceWithTwoArguments),
@@ -66,16 +65,11 @@ class RuntimeArgumentsTests: XCTestCase {
      ("testThatNewRegistrationWithSameArgumentsOverridesPreviousRegistration", testThatNewRegistrationWithSameArgumentsOverridesPreviousRegistration),
      ("testThatDifferentFactoriesRegisteredIfArgumentIsOptional", testThatDifferentFactoriesRegisteredIfArgumentIsOptional)
    ]
-  }
+  }()

-  func setUp() {
-    container.reset()
-  }
-  #else
  override func setUp() {
    container.reset()
  }
-  #endif
  
  func testThatItResolvesInstanceWithOneArgument() {
    //given
@@ -86,10 +80,16 @@ class RuntimeArgumentsTests: XCTestCase {
    })
    
    //when
-    let service = try! container.resolve(withArguments: arg1) as Service
+    let service = try! container.resolve(arguments: arg1) as Service
    
    //then
    XCTAssertTrue(service is ServiceImp1)
+    
+    //when
+    let anyService = try! container.resolve(Service.self, arguments: arg1)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
  }
  
  func testThatItResolvesInstanceWithTwoArguments() {
@@ -102,10 +102,16 @@ class RuntimeArgumentsTests: XCTestCase {
    }
    
    //when
-    let service = try! container.resolve(withArguments: arg1, arg2) as Service
+    let service = try! container.resolve(arguments: arg1, arg2) as Service
    
    //then
    XCTAssertTrue(service is ServiceImp1)
+
+    //when
+    let anyService = try! container.resolve(Service.self, arguments: arg1, arg2)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
  }
  
  func testThatItResolvesInstanceWithThreeArguments() {
@@ -118,10 +124,16 @@ class RuntimeArgumentsTests: XCTestCase {
    }
    
    //when
-    let service = try! container.resolve(withArguments: arg1, arg2, arg3) as Service
+    let service = try! container.resolve(arguments: arg1, arg2, arg3) as Service
    
    //then
    XCTAssertTrue(service is ServiceImp1)
+    
+    //when
+    let anyService = try! container.resolve(Service.self, arguments: arg1, arg2, arg3)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
  }
  
  func testThatItResolvesInstanceWithFourArguments() {
@@ -135,10 +147,16 @@ class RuntimeArgumentsTests: XCTestCase {
    }
    
    //when
-    let service = try! container.resolve(withArguments: arg1, arg2, arg3, arg4) as Service
+    let service = try! container.resolve(arguments: arg1, arg2, arg3, arg4) as Service
    
    //then
    XCTAssertTrue(service is ServiceImp1)
+    
+    //when
+    let anyService = try! container.resolve(Service.self, arguments: arg1, arg2, arg3, arg4)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
  }
  
  func testThatItResolvesInstanceWithFiveArguments() {
@@ -153,10 +171,16 @@ class RuntimeArgumentsTests: XCTestCase {
    }
    
    //when
-    let service = try! container.resolve(withArguments: arg1, arg2, arg3, arg4, arg5) as Service
+    let service = try! container.resolve(arguments: arg1, arg2, arg3, arg4, arg5) as Service
    
    //then
    XCTAssertTrue(service is ServiceImp1)
+    
+    //when
+    let anyService = try! container.resolve(Service.self, arguments: arg1, arg2, arg3, arg4, arg5)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
  }
  
  func testThatItResolvesInstanceWithSixArguments() {
@@ -172,10 +196,16 @@ class RuntimeArgumentsTests: XCTestCase {
    }
    
    //when
-    let service = try! container.resolve(withArguments: arg1, arg2, arg3, arg4, arg5, arg6) as Service
+    let service = try! container.resolve(arguments: arg1, arg2, arg3, arg4, arg5, arg6) as Service
    
    //then
    XCTAssertTrue(service is ServiceImp1)
+    
+    //when
+    let anyService = try! container.resolve(Service.self, arguments: arg1, arg2, arg3, arg4, arg5, arg6)
+    
+    //then
+    XCTAssertTrue(anyService is ServiceImp1)
  }
  
  func testThatItRegistersDifferentFactoriesForDifferentNumberOfArguments() {
@@ -185,8 +215,8 @@ class RuntimeArgumentsTests: XCTestCase {
    container.register { (a1: Int, a2: Int) in ServiceImp2() as Service }
    
    //when
-    let service1 = try! container.resolve(withArguments: arg1) as Service
-    let service2 = try! container.resolve(withArguments: arg1, arg2) as Service
+    let service1 = try! container.resolve(arguments: arg1) as Service
+    let service2 = try! container.resolve(arguments: arg1, arg2) as Service
    
    //then
    XCTAssertTrue(service1 is ServiceImp1)
@@ -200,8 +230,8 @@ class RuntimeArgumentsTests: XCTestCase {
    container.register(factory: { (a1: String) in ServiceImp2() as Service })
    
    //when
-    let service1 = try! container.resolve(withArguments: arg1) as Service
-    let service2 = try! container.resolve(withArguments: arg2) as Service
+    let service1 = try! container.resolve(arguments: arg1) as Service
+    let service2 = try! container.resolve(arguments: arg2) as Service
    
    //then
    XCTAssertTrue(service1 is ServiceImp1)
@@ -215,8 +245,8 @@ class RuntimeArgumentsTests: XCTestCase {
    container.register { (a1: String, a2: Int) in ServiceImp2() as Service }
    
    //when
-    let service1 = try! container.resolve(withArguments: arg1, arg2) as Service
-    let service2 = try! container.resolve(withArguments: arg2, arg1) as Service
+    let service1 = try! container.resolve(arguments: arg1, arg2) as Service
+    let service2 = try! container.resolve(arguments: arg2, arg1) as Service
    
    //then
    XCTAssertTrue(service1 is ServiceImp1)
@@ -227,11 +257,11 @@ class RuntimeArgumentsTests: XCTestCase {
    //given
    let arg1 = 1, arg2 = 2
    container.register { (a1: Int, a2: Int) in ServiceImp1() as Service }
-    let service1 = try! container.resolve(withArguments: arg1, arg2) as Service
+    let service1 = try! container.resolve(arguments: arg1, arg2) as Service
    
    //when
    container.register { (a1: Int, a2: Int) in ServiceImp2() as Service }
-    let service2 = try! container.resolve(withArguments: arg1, arg2) as Service
+    let service2 = try! container.resolve(arguments: arg1, arg2) as Service
    
    //then
    XCTAssertTrue(service1 is ServiceImp1)
@@ -240,20 +270,28 @@ class RuntimeArgumentsTests: XCTestCase {
  
  func testThatDifferentFactoriesRegisteredIfArgumentIsOptional() {
    //given
-    let name1 = "1", name2 = "2", name3 = "3"
+    let name1 = "1", name2 = "2"
    container.register { (port: Int, url: String) in ServiceImp(name: name1, baseURL: url, port: port) as Service }
    container.register { (port: Int, url: String?) in ServiceImp(name: name2, baseURL: url!, port: port) as Service }
-    container.register { (port: Int, url: String!) in ServiceImp(name: name3, baseURL: url, port: port) as Service }
    
    //when
-    let service1 = try! container.resolve(withArguments: 80, "http://example.com") as Service
-    let service2 = try! container.resolve(withArguments: 80, "http://example.com" as String?) as Service
-    let service3 = try! container.resolve(withArguments: 80, "http://example.com" as String!) as Service
+    let service1 = try! container.resolve(arguments: 80, "http://example.com") as Service
+    let service2 = try! container.resolve(arguments: 80, "http://example.com" as String?) as Service
    
    //then
    XCTAssertEqual(service1.name, name1)
    XCTAssertEqual(service2.name, name2)
-    XCTAssertEqual(service3.name, name3)
+    
+    //Due to incomplete implementation of SE-0054 (bug: https://bugs.swift.org/browse/SR-2143)
+    //registering definition with T? and T! arguments types will produce two different definitions
+    //but when argement of T! will be passed to `resolve` method it will be transformed to T?
+    //and wrong definition will be used
+    //When fixed using T? and T! should not register two different definitions
+
+//    let name3 = "3"
+//    container.register { (port: Int, url: String!) in ServiceImp(name: name3, baseURL: url, port: port) as Service }
+//    let service3 = try! container.resolve(arguments: 80, "http://example.com" as String!) as Service
+//    XCTAssertEqual(service3.name, name3)
  }
  
 }
@@ -26,7 +26,7 @@ import XCTest
@testable import Dip

 private protocol Server: class {
-  var client: Client? { get set }
+  var client: Client! { get set }
 }

 private protocol Client: class {
@@ -45,11 +45,11 @@ private func ==<T: ClientImp>(lhs: T, rhs: T) -> Bool {
 }

 private class ServerImp: Server, Hashable {
-  weak var client: Client?
+  weak var client: Client!
  init() {}
  
  var hashValue: Int {
-    return unsafeAddressOf(self).hashValue
+    return Unmanaged.passUnretained(self).toOpaque().hashValue
  }
 }

@@ -64,24 +64,26 @@ private var container: DependencyContainer!

 #if os(Linux)
 import Glibc
+  
+private var runningThreads: Int = 0
 private var lock: pthread_spinlock_t = 0

 private let resolveClientSync: () -> Client? = {
-  var clientPointer: UnsafeMutablePointer<Void> = nil
-  clientPointer = dispatch_sync { _ in
+  let pointer = dispatch_sync { _ in
    let resolved = try! container.resolve() as Client
-    return UnsafeMutablePointer(Unmanaged.passUnretained(resolved as! ClientImp).toOpaque())
+    return UnsafeMutableRawPointer(Unmanaged.passRetained(resolved as! ClientImp).toOpaque())
  }
-  return Unmanaged<ClientImp>.fromOpaque(COpaquePointer(clientPointer)).takeUnretainedValue()
+  guard let clientPointer = pointer else { return nil }
+  return Unmanaged<ClientImp>.fromOpaque(clientPointer).takeRetainedValue()
 }
  
 #else
-let queue = NSOperationQueue()
-let lock = NSRecursiveLock()
+let queue = OperationQueue()
+let lock = RecursiveLock()
  
 private let resolveClientSync: () -> Client? = {
  var client: Client?
-  dispatch_sync(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)) {
+  DispatchQueue.global(qos: .default).sync() {
    client = try! container.resolve() as Client
  }
  return client
@@ -90,9 +92,14 @@ private let resolveClientSync: () -> Client? = {
 #endif

 let resolveServerAsync = {
-  let service = try! container.resolve() as Server
+  let server = try! container.resolve() as Server
  lock.lock()
-  resolvedServers.insert(service as! ServerImp)
+  resolvedServers.insert(server as! ServerImp)
+
+  #if os(Linux)
+    runningThreads -= 1
+  #endif
+
  lock.unlock()
 }

@@ -100,34 +107,33 @@ let resolveClientAsync = {
  let client = try! container.resolve() as Client
  lock.lock()
  resolvedClients.append(client as! ClientImp)
+
+  #if os(Linux)
+    runningThreads -= 1
+  #endif
+
  lock.unlock()
 }

 class ThreadSafetyTests: XCTestCase {
  
  #if os(Linux)
-  init() {
+  required init(name: String, testClosure: @escaping (XCTestCase) throws -> Void) {
    pthread_spin_init(&lock, 0)
+    super.init(name: name, testClosure: testClosure)
  }
+  #endif
  
-  var allTests: [(String, () throws -> Void)] {
+  static var allTests = {
    return [
      ("testSingletonThreadSafety", testSingletonThreadSafety),
      ("testFactoryThreadSafety", testFactoryThreadSafety),
      ("testCircularReferenceThreadSafety", testCircularReferenceThreadSafety)
    ]
-  }
+  }()
  
-  func setUp() {
-    container = DependencyContainer()
-  }
-  
-  func tearDown() {
-    resolvedServers.removeAll()
-    resolvedClients.removeAll()
-  }
-  #else
  override func setUp() {
+    Dip.logLevel = .Verbose
    container = DependencyContainer()
  }
  
@@ -135,24 +141,27 @@ class ThreadSafetyTests: XCTestCase {
    resolvedServers.removeAll()
    resolvedClients.removeAll()
  }
-  #endif
  
  func testSingletonThreadSafety() {
-    container.register(.Singleton) { ServerImp() as Server }
+    container.register(.singleton) { ServerImp() as Server }
    
    for _ in 0..<100 {
      #if os(Linux)
-      dispatch_async({ _ in
+      lock.lock()
+      runningThreads += 1
+      lock.unlock()
+        
+      dispatch_async { _ in
        resolveServerAsync()
        return nil
-      })
+      }
      #else
-      queue.addOperationWithBlock(resolveServerAsync)
+      queue.addOperation(resolveServerAsync)
      #endif
    }
    
    #if os(Linux)
-    sleep(1)
+    while runningThreads > 0 { sleep(1) }
    #else
    queue.waitUntilAllOperationsAreFinished()
    #endif
@@ -166,17 +175,21 @@ class ThreadSafetyTests: XCTestCase {
    
    for _ in 0..<100 {
      #if os(Linux)
-      dispatch_async({ _ in
+      lock.lock()
+      runningThreads += 1
+      lock.unlock()
+
+      dispatch_async { _ in
        resolveServerAsync()
        return nil
-      })
+      }
      #else
-      queue.addOperationWithBlock(resolveServerAsync)
+      queue.addOperation(resolveServerAsync)
      #endif
    }
    
    #if os(Linux)
-    sleep(1)
+    while runningThreads > 0 { sleep(1) }
    #else
    queue.waitUntilAllOperationsAreFinished()
    #endif
@@ -186,28 +199,32 @@ class ThreadSafetyTests: XCTestCase {
  
  
  func testCircularReferenceThreadSafety() {
-    container.register(.ObjectGraph) {
+    container.register {
      ClientImp(server: try container.resolve()) as Client
    }
    
-    container.register(.ObjectGraph) { ServerImp() as Server }
-      .resolveDependencies { container, server in
+    container.register { ServerImp() as Server }
+      .resolvingProperties { container, server in
        server.client = resolveClientSync()
    }
    
    for _ in 0..<100 {
      #if os(Linux)
-      dispatch_async({ _ in
+      lock.lock()
+      runningThreads += 1
+      lock.unlock()
+
+      dispatch_async { _ in
        resolveClientAsync()
        return nil
-      })
+      }
      #else
-      queue.addOperationWithBlock(resolveClientAsync)
+      queue.addOperation(resolveClientAsync)
      #endif
    }
    
    #if os(Linux)
-    sleep(1)
+    while runningThreads > 0 { sleep(1) }
    #else
    queue.waitUntilAllOperationsAreFinished()
    #endif
@@ -0,0 +1,345 @@
+//
+// Dip
+//
+// Copyright (c) 2015 Olivier Halligon <olivier@halligon.net>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+import XCTest
+@testable import Dip
+
+private protocol Service: class { }
+private protocol ForwardedType: class { }
+private class ServiceImp1: NSObject, Service, ForwardedType { }
+private class ServiceImp2: NSObject, Service, ForwardedType { }
+
+class TypeForwardingTests: XCTestCase {
+  
+  let container = DependencyContainer()
+
+  static var allTests = {
+    return [
+      ("testThatItResolvesInstanceByTypeForwarding", testThatItResolvesInstanceByTypeForwarding),
+      ("testThatItReusesInstanceResolvedByTypeForwarding", testThatItReusesInstanceResolvedByTypeForwarding),
+      ("testThatItDoesNotResolveByTypeForwardingIfRegisteredForAnotherTag", testThatItDoesNotResolveByTypeForwardingIfRegisteredForAnotherTag),
+      ("testThatItDoesNotReuseInstanceResolvedByTypeForwardingRegisteredForAnotherTag",  testThatItDoesNotReuseInstanceResolvedByTypeForwardingRegisteredForAnotherTag),
+      ("testThatItCallsResolvedDependenciesBlockWhenResolvingByTypeForwarding", testThatItCallsResolvedDependenciesBlockWhenResolvingByTypeForwarding),
+      ("testThatItCallsResolvedDependenciesBlockProvidedAfterRegistrationWhenResolvingByTypeForwarding",testThatItCallsResolvedDependenciesBlockProvidedAfterRegistrationWhenResolvingByTypeForwarding),
+      ("testThatItFallbackToDefinitionWithNoTagWhenResolvingInstanceByTypeForwarding", testThatItFallbackToDefinitionWithNoTagWhenResolvingInstanceByTypeForwarding),
+      ("testThatItCanResolveOptional", testThatItCanResolveOptional),
+      ("testThatItFirstUsesTaggedDefinitionWhenResolvingOptional", testThatItFirstUsesTaggedDefinitionWhenResolvingOptional),
+      ("testThatItThrowsErrorWhenResolvingNotImplementedTypeWithTypeForwarding", testThatItThrowsErrorWhenResolvingNotImplementedTypeWithTypeForwarding),
+      ("testThatItOverridesIfSeveralDefinitionsWithTheSameTagForwardTheSameType", testThatItOverridesIfSeveralDefinitionsWithTheSameTagForwardTheSameType),
+      ("testThatItDoesNotOverrideIfDefinitionForwardsTheSameTypeWithDifferentTag", testThatItDoesNotOverrideIfDefinitionForwardsTheSameTypeWithDifferentTag)
+    ]
+  }()
+  
+  override func setUp() {
+    container.reset()
+  }
+  
+  func testThatItResolvesInstanceByTypeForwarding() {
+    //given
+    container.register { ServiceImp1() as Service }
+      .implements(ForwardedType.self)
+      .implements(NSObject.self)
+    
+    //when
+    let anotherService = try! container.resolve() as ForwardedType
+    let anyOtherService = try! container.resolve(ForwardedType.self)
+    let object = try! container.resolve() as NSObject
+    let anyObject = try! container.resolve(NSObject.self)
+    
+    //then
+    XCTAssertTrue(anotherService is ServiceImp1)
+    XCTAssertTrue(object is ServiceImp1)
+    XCTAssertTrue(anyOtherService is ServiceImp1)
+    XCTAssertTrue(anyObject is ServiceImp1)
+  }
+  
+  func testThatItReusesInstanceResolvedByTypeForwarding() {
+    //given
+    container.register() { ServiceImp1() as Service }
+      .resolvingProperties { container, resolved in
+        //when
+        //resolving forwarded type
+        let forwardType = try container.resolve() as ForwardedType
+        let anyForwardType = try container.resolve(ForwardedType.self) as! ForwardedType
+        let object = try container.resolve() as NSObject
+        let anyObject = try container.resolve(NSObject.self) as! NSObject
+        let service = try container.resolve() as Service
+        let anyService = try container.resolve(Service.self) as! Service
+
+        //then
+        XCTAssertTrue(forwardType === resolved as! ForwardedType)
+        XCTAssertTrue(anyForwardType === resolved as! ForwardedType)
+        XCTAssertTrue(object === resolved as! NSObject)
+        XCTAssertTrue(anyObject === resolved as! NSObject)
+        XCTAssertTrue(service === resolved)
+        XCTAssertTrue(anyService === resolved)
+      }
+      .implements(ForwardedType.self)
+      .implements(NSObject.self)
+    
+    let _ = try! container.resolve() as Service
+    let _ = try! container.resolve() as ForwardedType
+//    let _ = try! container.resolve() as NSObject
+  }
+  
+  func testThatItDoesNotResolveByTypeForwardingIfRegisteredForAnotherTag() {
+    //given
+    let def = container.register(tag: "tag") { ServiceImp1() as Service }
+    def.implements(ForwardedType.self, tag: "otherTag")
+    
+    //then
+    AssertThrows(expression: try container.resolve(tag: "tag") as ForwardedType)
+    AssertThrows(expression: try container.resolve(ForwardedType.self, tag: "tag"))
+    
+    //and given
+    def.implements(ForwardedType.self, tag: "tag")
+    
+    //then
+    AssertNoThrow(expression: try container.resolve(tag: "tag") as ForwardedType)
+    AssertNoThrow(expression: try container.resolve(ForwardedType.self, tag: "tag"))
+  }
+  
+  func testThatItDoesNotReuseInstanceResolvedByTypeForwardingRegisteredForAnotherTag() {
+    var resolveDependenciesCalled = false
+    //given
+    container.register() { ServiceImp1() as Service }
+      .resolvingProperties { container, service in
+        guard resolveDependenciesCalled == false else { return }
+        resolveDependenciesCalled = true
+
+        //when
+        //resolving via type-forawrding for tag different then tag for original definition
+        let forwardType = try container.resolve(tag: "tag") as ForwardedType
+        let anyForwardType = try container.resolve(ForwardedType.self, tag: "tag") as! ForwardedType
+
+        let object = try container.resolve() as NSObject
+        let anyObject = try container.resolve(NSObject.self) as! NSObject
+        
+        //then
+        XCTAssertFalse(forwardType === service as! ForwardedType)
+        XCTAssertFalse(anyForwardType === service as! ForwardedType)
+        XCTAssertTrue(object === service as! NSObject)
+        XCTAssertTrue(anyObject === service as! NSObject)
+      }
+      .implements(ForwardedType.self, tag: "tag")
+      .implements(NSObject.self)
+    
+    //when
+    let _ = try! container.resolve() as Service
+  }
+  
+  func testThatItCallsResolvedDependenciesBlockWhenResolvingByTypeForwarding() {
+    //given
+    var originalResolvingPropertiesCalled = false
+    var resolvingPropertiesCalled = false
+    container.register { ServiceImp1() }
+      .resolvingProperties { _,_  in
+        originalResolvingPropertiesCalled = true
+      }.implements(Service.self) { _,_ in
+        resolvingPropertiesCalled = true
+      }
+    
+    //when
+    let _ = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(resolvingPropertiesCalled)
+    XCTAssertTrue(originalResolvingPropertiesCalled)
+
+    //and when
+    resolvingPropertiesCalled = false
+    originalResolvingPropertiesCalled = false
+    let _ = try! container.resolve(Service.self)
+    
+    //then
+    XCTAssertTrue(resolvingPropertiesCalled)
+    XCTAssertTrue(originalResolvingPropertiesCalled)
+  }
+  
+  func testThatItCallsResolvedDependenciesBlockProvidedAfterRegistrationWhenResolvingByTypeForwarding() {
+    //given
+    //resolvingProperties provided after registering definition
+    var originalResolvingPropertiesCalled = false
+    var resolvingPropertiesCalled = false
+    container.reset()
+    let definition = container.register { ServiceImp1() }
+      .implements(Service.self) { _,_ in
+        resolvingPropertiesCalled = true
+    }
+    
+    definition.resolvingProperties { _,_  in
+      originalResolvingPropertiesCalled = true
+    }
+    
+    //when
+    let _ = try! container.resolve() as Service
+    
+    //then
+    XCTAssertTrue(resolvingPropertiesCalled)
+    XCTAssertTrue(originalResolvingPropertiesCalled)
+
+    //and when
+    resolvingPropertiesCalled = false
+    originalResolvingPropertiesCalled = false
+    let _ = try! container.resolve(Service.self)
+    
+    //then
+    XCTAssertTrue(resolvingPropertiesCalled)
+    XCTAssertTrue(originalResolvingPropertiesCalled)
+  }
+  
+  func testThatItFallbackToDefinitionWithNoTagWhenResolvingInstanceByTypeForwarding() {
+    //given
+    container.register { ServiceImp1() as Service }
+      .implements(ForwardedType.self)
+    
+    //when
+    let service = try! container.resolve(tag: "tag") as ForwardedType
+    let anyService = try! container.resolve(ForwardedType.self, tag: "tag")
+    
+    //then
+    XCTAssertTrue(service is ServiceImp1)
+    XCTAssertTrue(anyService is ServiceImp1)
+  }
+  
+  func testThatItCanResolveOptional() {
+    container.register { ServiceImp1() as Service }
+      .implements(ForwardedType.self)
+      .implements(NSObject.self)
+    
+    //when
+    let service = try! container.resolve() as Service?
+    let anyService = try! container.resolve((Service?).self)
+    
+    //then
+    XCTAssertTrue(service is ServiceImp1)
+    XCTAssertTrue(anyService is ServiceImp1)
+
+    //when
+    let forwardedType = try! container.resolve() as ForwardedType?
+    let anyForwardedType = try! container.resolve((ForwardedType?).self)
+    
+    //then
+    XCTAssertTrue(forwardedType is ServiceImp1)
+    XCTAssertTrue(anyForwardedType is ServiceImp1)
+  
+    //when
+    let object = try! container.resolve() as NSObject?
+    let anyObject = try! container.resolve((NSObject?).self)
+    
+    //then
+    XCTAssertTrue(object is ServiceImp1)
+    XCTAssertTrue(anyObject is ServiceImp1)
+  }
+  
+  func testThatItFirstUsesTaggedDefinitionWhenResolvingOptional() {
+    let expectedTag: DependencyContainer.Tag = .String("tag")
+    container.register(tag: expectedTag) { ServiceImp1() as Service }
+      .resolvingProperties { container, resolved in
+        XCTAssertEqual(container.context.tag, expectedTag)
+    }
+    container.register { ServiceImp2() as Service }
+    
+    //when
+    let service = try! container.resolve(tag: "tag") as Service?
+    let anyService = try! container.resolve((Service?).self, tag: "tag")
+    
+    //then
+    XCTAssertTrue(service is ServiceImp1)
+    XCTAssertTrue(anyService is ServiceImp1)
+  }
+  
+  func testThatItThrowsErrorWhenResolvingNotImplementedTypeWithTypeForwarding() {
+    //given
+    container.register { ServiceImp1() as Service }
+      .implements(ServiceImp2.self)
+    
+    //then
+    AssertThrows(expression: try container.resolve() as ServiceImp2) { error in
+      guard case let DipError.invalidType(_, key) = error else { return false }
+      
+      let expectedKey = DefinitionKey(type: ServiceImp2.self, typeOfArguments: Void.self, tag: nil)
+      XCTAssertEqual(key, expectedKey)
+      return true
+    }
+    AssertThrows(expression: try container.resolve(ServiceImp2.self)) { error in
+      guard case let DipError.invalidType(_, key) = error else { return false }
+      
+      let expectedKey = DefinitionKey(type: ServiceImp2.self, typeOfArguments: Void.self, tag: nil)
+      XCTAssertEqual(key, expectedKey)
+      return true
+    }
+  }
+  
+  func testThatItOverridesIfSeveralDefinitionsWithTheSameTagForwardTheSameType() {
+    let def1 = container.register { ServiceImp1() }
+    let def2 = container.register { ServiceImp2() }
+    
+    //when
+    def1.implements(ForwardedType.self)
+
+    //then
+    XCTAssertTrue(try! container.resolve() as ForwardedType is ServiceImp1)
+    XCTAssertTrue(try! container.resolve(ForwardedType.self) is ServiceImp1)
+
+    //when
+    //another definition implements the same type
+    def2.implements(ForwardedType.self)
+    
+    //then
+    XCTAssertTrue(try! container.resolve() as ForwardedType is ServiceImp2)
+    XCTAssertTrue(try! container.resolve(ForwardedType.self) is ServiceImp2)
+    
+    //when
+    def1.implements(ForwardedType.self, tag: "tag")
+
+    //then
+    XCTAssertTrue(try! container.resolve(tag: "tag") as ForwardedType is ServiceImp1)
+    XCTAssertTrue(try! container.resolve(ForwardedType.self, tag: "tag") is ServiceImp1)
+
+    //when
+    //another definition implements the same type for the same tag
+    def2.implements(ForwardedType.self, tag: "tag")
+    
+    //then
+    XCTAssertTrue(try! container.resolve(tag: "tag") as ForwardedType is ServiceImp2)
+    XCTAssertTrue(try! container.resolve(ForwardedType.self, tag: "tag") is ServiceImp2)
+    
+  }
+  
+  func testThatItDoesNotOverrideIfDefinitionForwardsTheSameTypeWithDifferentTag() {
+    let def1 = container.register { ServiceImp1() }
+    let def2 = container.register { ServiceImp2() }
+
+    //when
+    def1.implements(ForwardedType.self, tag: "tag")
+    //another definition implements the same type for a different tag
+    def2.implements(ForwardedType.self, tag: "anotherTag")
+    
+    //then
+    XCTAssertTrue(try! container.resolve(tag: "tag") as ForwardedType is ServiceImp1)
+    XCTAssertTrue(try! container.resolve(ForwardedType.self, tag: "tag") is ServiceImp1)
+  }
+  
+}
@@ -25,27 +25,24 @@
 import XCTest

 #if os(Linux)
-typealias FileString = StaticString
-#else
-typealias FileString = String
+  typealias NSObject = AnyObject
 #endif
-  

-func AssertThrows<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoclosure expression: () throws -> T) {
+func AssertThrows<T>(_ file: StaticString = #file, line: UInt = #line, expression: @autoclosure () throws -> T) {
  AssertThrows(file, line: line, expression: expression, "")
 }

-func AssertThrows<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoclosure expression: () throws -> T, _ message: String) {
+func AssertThrows<T>(_ file: StaticString = #file, line: UInt = #line, expression: @autoclosure () throws -> T, _ message: String) {
  AssertThrows(expression: expression, checkError: { _ in true }, message)
 }

-func AssertThrows<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoclosure expression: () throws -> T, checkError: ErrorType -> Bool) {
+func AssertThrows<T>(_ file: StaticString = #file, line: UInt = #line, expression: @autoclosure () throws -> T, checkError: (Error) -> Bool) {
  AssertThrows(file, line: line, expression: expression, checkError: checkError, "")
 }

-func AssertThrows<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoclosure expression: () throws -> T, checkError: ErrorType -> Bool, _ message: String) {
+func AssertThrows<T>(_ file: StaticString = #file, line: UInt = #line, expression: @autoclosure () throws -> T, checkError: (Error) -> Bool, _ message: String) {
  do {
-    try expression()
+    let _ = try expression()
    XCTFail(message, file: file, line: line)
  }
  catch {
@@ -53,13 +50,13 @@ func AssertThrows<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autocl
  }
 }

-func AssertNoThrow<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoclosure expression: () throws -> T) {
+func AssertNoThrow<T>(_ file: StaticString = #file, line: UInt = #line, expression: @autoclosure () throws -> T) {
  AssertNoThrow(file, line: line, expression: expression, "")
 }

-func AssertNoThrow<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoclosure expression: () throws -> T, _ message: String) {
+func AssertNoThrow<T>(_ file: StaticString = #file, line: UInt = #line, expression: @autoclosure () throws -> T, _ message: String) {
  do {
-    try expression()
+    let _ = try expression()
  }
  catch {
    XCTFail(message, file: file, line: line)
@@ -68,17 +65,21 @@ func AssertNoThrow<T>(file: FileString = __FILE__, line: UInt = __LINE__, @autoc

 #if os(Linux)
 import Glibc
-typealias TMain = @convention(c) (UnsafeMutablePointer<Void>) -> UnsafeMutablePointer<Void>
+typealias TMain = @convention(c) (UnsafeMutableRawPointer?) -> UnsafeMutableRawPointer?

-func dispatch_async(block: TMain) {
+private func startThread(_ block: @escaping TMain) -> pthread_t  {
  var pid: pthread_t = 0
  pthread_create(&pid, nil, block, nil)
+  return pid
 }

-func dispatch_sync(block: TMain) -> UnsafeMutablePointer<Void> {
-  var pid: pthread_t = 0
-  var result: UnsafeMutablePointer<Void> = nil
-  pthread_create(&pid, nil, block, nil)
+func dispatch_async(block: @escaping TMain) -> pthread_t {
+  return startThread(block)
+}
+
+func dispatch_sync(block: @escaping TMain) -> UnsafeMutableRawPointer? {
+  var result: UnsafeMutableRawPointer? = UnsafeMutableRawPointer.allocate(bytes: 1, alignedTo: 0)
+  let pid = startThread(block)
  pthread_join(pid, &result)
  return result
 }
@@ -0,0 +1,14 @@
+import XCTest
+@testable import DipTests
+
+XCTMain([
+  testCase(DipTests.allTests),
+  testCase(DefinitionTests.allTests),
+  testCase(RuntimeArgumentsTests.allTests),
+  testCase(ComponentScopeTests.allTests),
+  testCase(AutoInjectionTests.allTests),
+//  testCase(ThreadSafetyTests.allTests),
+  testCase(AutoWiringTests.allTests),
+  testCase(ContextTests.allTests),
+  testCase(TypeForwardingTests.allTests)
+])