Enable strings to run commands using themselves as standard input.

SwiftShell/General/String.swift

@@ -7,3 +7,15 @@
 
 import Foundation
 
+/** Let Strings run commands using itself as stdin. */
+extension String: ShellRunnable {
+	public var shellcontext: ShellContextType {
+		var context = ShellContext(main)
+		let (writer,reader) = streams()
+
+		writer.write(self)
+		writer.close()
+		context.stdin = reader
+		return context
+	}
+}

SwiftShellTests/General/String_Tests.swift

@@ -11,4 +11,8 @@ import SwiftShell
 
 class String_Tests: XCTestCase {
 
+	func testRunCommands () {
+		XCTAssertEqual("one two".run("wc","-w"), "2")
+		XCTAssertEqual("one".runAsync("cat").stdout.read(), "one")
+	}
 }