nordic-dev.net/nixpkgs
nordic-dev.net/nixpkgs
2
0
Fork 0
mirror of https://github.com/NixOS/nixpkgs.git synced 2025-02-01 17:53:14 +00:00
Code Issues Packages Projects Releases Wiki Activity

haskellPackages.callPackage: support returning functions

Browse Source 
Overrideable functions are possible by wrapping them as functors in an
attribute set first and appending the overrideScope and override
attributes later.
This commit is contained in:
sternenseemann 2021-11-20 16:31:02 +01:00 committed by sterni
parent f662c8be61
commit baaf9459d6
1 changed files with 4 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
pkgs/development/haskell-modules/make-package-set.nix
View File

@ -87,8 +87,11 @@ let
drv = if lib.isFunction fn then fn else import fn; drv = if lib.isFunction fn then fn else import fn;
auto = builtins.intersectAttrs (lib.functionArgs drv) scope; auto = builtins.intersectAttrs (lib.functionArgs drv) scope;
# Converts a returned function to a functor attribute set if necessary
ensureAttrs = v: if builtins.isFunction v then { __functor = _: v; } else v;
# this wraps the `drv` function to add a `overrideScope` function to the result. # this wraps the `drv` function to add a `overrideScope` function to the result.
drvScope = allArgs: drv allArgs // { drvScope = allArgs: ensureAttrs (drv allArgs) // {
overrideScope = f: overrideScope = f:
let newScope = mkScope (fix' (extends f scope.__unfix__)); let newScope = mkScope (fix' (extends f scope.__unfix__));
# note that we have to be careful here: `allArgs` includes the auto-arguments that # note that we have to be careful here: `allArgs` includes the auto-arguments that