mirror of
https://github.com/simplex-chat/haskell.nix.git
synced 2026-06-03 09:17:32 +00:00
paumr
a045d79264
After investigating adding a project argument to override the mapping of libs to packages we realised we could fix the X11 package by updating `modules/configuration-nix.nix`. We also updated `system-nixpkgs-map.nix` to allow multiple packages to be mapped for a single library (turned out not to be necessary for X11). Co-authored-by: Rodney Lorrimar <rodney.lorrimar@iohk.io> Co-authored-by: Hamish Mackenzie <Hamish.Mackenzie@iohk.io>
69 lines
2.4 KiB
Markdown
69 lines
2.4 KiB
Markdown
# Mapping non-Haskell dependencies to Nixpkgs
|
|
|
|
Cabal files may contain dependencies to external non-Haskell
|
|
dependencies via:
|
|
|
|
* [`build-tool-depends`](https://cabal.readthedocs.io/en/latest/developing-packages.html#pkg-field-build-tool-depends)
|
|
* [`pkgconfig-depends`](https://cabal.readthedocs.io/en/latest/developing-packages.html#pkg-field-pkgconfig-depends)
|
|
* [`frameworks`](https://cabal.readthedocs.io/en/latest/developing-packages.html#pkg-field-frameworks)
|
|
* [`extra-libraries`](https://cabal.readthedocs.io/en/latest/developing-packages.html#pkg-field-extra-libraries)
|
|
|
|
If there is a `pkgs` attribute in Nixpkgs that matches the name given
|
|
in the Cabal file, then it will be added as a dependency (see the
|
|
output of `cabal-to-nix`). Otherwise, there needs to be a mapping from
|
|
Cabal file names (decided by the package author) to Nix package
|
|
identifiers.
|
|
|
|
### Nixpkgs overlay
|
|
|
|
The user may solve it by themself by overriding Nixpkgs and adding a
|
|
package alias. For example:
|
|
|
|
```nix
|
|
nixpkgs.overlays = [
|
|
(self: super: {
|
|
icuuc = self.icu;
|
|
icui18n = self.icu;
|
|
icudata = self.icu;
|
|
})
|
|
];
|
|
```
|
|
|
|
### Replace libraries of components
|
|
|
|
If a component is missing a dependency it can be added via modules. For example:
|
|
|
|
``` nix
|
|
project = pkgs.haskell-nix.project' {
|
|
src = self;
|
|
compiler-nix-name = "ghc8102";
|
|
modules = [{
|
|
# Replace `extra-libraries` dependencies
|
|
packages.X11.components.library.libs = pkgs.lib.mkForce (with pkgs.xorg;
|
|
[ libX11 libXrandr libXext libXScrnSaver libXinerama ]);
|
|
}];
|
|
};
|
|
```
|
|
|
|
### Mapping in Haskell.nix
|
|
|
|
Alternatively, if the name is commonly used, an alias can be added to
|
|
the Haskell.nix sources, so that it's solved for all users.
|
|
|
|
* [`lib/pkgconf-nixpkgs-map.nix`](https://github.com/input-output-hk/haskell.nix/blob/master/lib/pkgconf-nixpkgs-map.nix)
|
|
— for `pkgconfig-depends`.
|
|
|
|
Each mapping entry is a list of packages.
|
|
|
|
* [`lib/system-nixpkgs-map.nix`](https://github.com/input-output-hk/haskell.nix/blob/master/lib/system-nixpkgs-map.nix)
|
|
— for `build-tool-depends`, `frameworks`, `extra-libraries`, etc.
|
|
|
|
Each name can be mapped to:
|
|
1. A single package from nixkpgs.
|
|
2. `null` — eliminates the dependency
|
|
3. A list of packages — sometimes needed for dependencies such as `X11`.
|
|
|
|
!!! tip "Open a PR"
|
|
Please go ahead and open a [pull request](https://github.com/input-output-hk/haskell.nix/pulls)
|
|
to improve the package mappings.
|