nixpkgs/nixos/modules/misc/nixpkgs.nix
Eelco Dolstra 29027fd1e1 Rewrite ‘with pkgs.lib’ -> ‘with lib’
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
2014-04-14 16:26:48 +02:00

78 lines
2 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
isConfig = x:
builtins.isAttrs x || builtins.isFunction x;
optCall = f: x:
if builtins.isFunction f
then f x
else f;
mergeConfig = lhs_: rhs_:
let
lhs = optCall lhs_ { inherit pkgs; };
rhs = optCall rhs_ { inherit pkgs; };
in
lhs // rhs //
optionalAttrs (lhs ? packageOverrides) {
packageOverrides = pkgs:
optCall lhs.packageOverrides pkgs //
optCall (attrByPath ["packageOverrides"] ({}) rhs) pkgs;
};
configType = mkOptionType {
name = "nixpkgs config";
check = traceValIfNot isConfig;
merge = args: fold (def: mergeConfig def.value) {};
};
in
{
options = {
nixpkgs.config = mkOption {
default = {};
example = literalExample
''
{ firefox.enableGeckoMediaPlayer = true;
packageOverrides = pkgs: {
firefox60Pkgs = pkgs.firefox60Pkgs.override {
enableOfficialBranding = true;
};
};
}
'';
type = configType;
description = ''
The configuration of the Nix Packages collection. (For
details, see the Nixpkgs documentation.) It allows you to set
package configuration options, and to override packages
globally through the <varname>packageOverrides</varname>
option. The latter is a function that takes as an argument
the <emphasis>original</emphasis> Nixpkgs, and must evaluate
to a set of new or overridden packages.
'';
};
nixpkgs.system = mkOption {
type = types.str;
description = ''
Specifies the Nix platform type for which NixOS should be built.
If unset, it defaults to the platform type of your host system
(<literal>${builtins.currentSystem}</literal>).
Specifying this option is useful when doing distributed
multi-platform deployment, or when building virtual machines.
'';
};
};
config = {
nixpkgs.system = mkDefault pkgs.stdenv.system;
};
}