Maximilian Bosch
e6a360a4d9
As described in #4745 it's otherwise fairly hard to understand where this is coming from. Say you have an expression which uses e.g. `types.package`: ``` nix { outputs = { self, nixpkgs }: { packages.x86_64-linux.hello = let foo = nixpkgs.lib.evalModules { modules = [ { options.foo.bar = with nixpkgs.lib; mkOption { type = types.package; }; } { foo.bar = ./.; } ]; }; in builtins.trace foo.config.foo.bar.outPath nixpkgs.legacyPackages.x86_64-linux.hello; defaultPackage.x86_64-linux = self.packages.x86_64-linux.hello; }; } ``` Then you'll get an error trace like this: ``` error: 'builtins.storePath' is not allowed in pure evaluation mode at /nix/store/p4h2x6r80njkb0j2rc1xjhhl99yri3zb-source/lib/attrsets.nix:328:15: 327| let 328| path' = builtins.storePath path; | ^ 329| res = … while evaluating the attribute 'config.foo.bar.outPath' at /nix/store/p4h2x6r80njkb0j2rc1xjhhl99yri3zb-source/lib/attrsets.nix:332:11: 331| name = sanitizeDerivationName (builtins.substring 33 (-1) (baseNameOf path')); 332| outPath = path'; | ^ 333| outputs = [ "out" ]; … while evaluating the attribute 'packages.x86_64-linux.hello' at /nix/store/6c1rfsqzrhjw1235palzjmf5vihcpci7-source/flake.nix:3:5: 2| { outputs = { self, nixpkgs }: { 3| packages.x86_64-linux.hello = let | ^ 4| foo = nixpkgs.lib.evalModules { ``` Fixes #4745
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