Without this patch merging options like
services.xserver.windowManager.xmonad.extraPackages
results in the evaluation error:
error: value is a list while a set was expected, at nixpkgs/lib/options.nix:77:23
With this patch we get the desired merging behaviour that just concatenates the
resulting package lists.
(cherry picked from commit 6e99f9fdecb1f28308c8e0aed0fc851737354864)
Co-Authored-By: Silvan Mosberger <contact@infinisil.com>
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.