hylonix/lib/default.nix

lib: {
  hylonix = {
    recursiveMerge =
      let
        f =
          x: y:
          if y == null then
            x
          else if builtins.typeOf x != builtins.typeOf y then
            y
          else if builtins.typeOf x == "set" then
            builtins.listToAttrs (
              builtins.map (name: {
                inherit name;
                value = f (x.${name} or null) (y.${name} or null);
              }) (builtins.attrNames y ++ builtins.attrNames x)
            )
          else if builtins.typeOf x == "list" then
            x ++ y
          else
            y;
      in
      f;

    recursiveMergeAll = builtins.foldl' lib.hylonix.recursiveMerge null;
  };

  inherit (lib.hylonix) recursiveMerge recursiveMergeAll;
}