flake.nix

   1 {
   2 #inputs.nixpkgs.url = "flake:nixpkgs"; # Reuse any local nixpkgs, at cost of reproductibility
   3 inputs.nixpkgs.url = "github:NixOS/nixpkgs/8585991bfb629edda1e42c191bef935d9d70d690";
   4 inputs.flake-utils.url = "github:numtide/flake-utils";
   5 outputs = inputs: inputs.flake-utils.lib.eachDefaultSystem (system: let
   6   pkgs = inputs.nixpkgs.legacyPackages.${system};
   7   ghc = null; # Use default ghc, but could have been ghc901
   8   haskellPackages =
   9     if ghc == null
  10     then pkgs.haskellPackages
  11     else pkgs.haskell.packages.${ghc};
  12   hs = haskellPackages.extend (with pkgs.haskell.lib; hfinal: hprev: {
  13     "AoC202004" = hfinal.callCabal2nix "AoC2020" ./Day04 {};
  14   });
  15   in rec {
  16     devShell = hs.shellFor {
  17       packages = p: [ p."AoC202004" ];
  18       withHoogle = false;
  19       nativeBuildInputs = [
  20         hs.cabal-install
  21         hs.haskell-language-server
  22         #hs.hpc
  23       ];
  24       buildInputs = [
  25         #hs.ghcid
  26         #hs.ormolu
  27         #hs.hlint
  28         #pkgs.nixpkgs-fmt
  29       ];
  30     };
  31     packages = {
  32       "Day04" = hs."AoC202004";
  33     };
  34     defaultApp = {
  35       type = "app";
  36       program = (pkgs.writeShellScript "run" ''
  37         cd ${inputs.self}
  38         ${pkgs.gnumake}/bin/make run
  39       '').outPath;
  40     };
  41     apps = pkgs.lib.genAttrs [
  42         "Day04"
  43       ] (day: {
  44         type = "app";
  45         program = "${packages.Day04}/bin/Day";
  46       }
  47     );
  48   }
  49 );
  50 }