flakes/lib/flake.nix

   1 {
   2   inputs.nixpkgs.url = "github:NixOS/nixpkgs";
   3
   4   description = "Useful libs";
   5   outputs = { self, nixpkgs }: {
   6     lib = rec {
   7       computeNarHash = path:
   8         let pkgs = import nixpkgs {};
   9         in
  10           builtins.readFile (pkgs.runCommand "narHash" {
  11             buildInputs = [ pkgs.nix ];
  12           } "echo -n $(nix hash-path ${path}) > $out");
  13
  14       withNarKeyCompat = flakeCompat: path: moduleAttrs:
  15         let module = (flakeCompat path).${moduleAttrs};
  16             narHash = computeNarHash path;
  17         in if builtins.isFunction module
  18           then args@{ config, lib, pkgs, ... }: (module args // { key = narHash; })
  19           else module // { key = narHash; };
  20
  21       withNarKey = dep: moduleAttrs:
  22         let module = dep.${moduleAttrs};
  23         in if builtins.isFunction module
  24           then args@{ config, lib, pkgs, ... }: (module args // { key = dep.narHash; })
  25           else module // { key = dep.narHash; };
  26     };
  27   };
  28 }