wlib main set documentation

wlib.evalModules

calls nixpkgs.lib.evalModules with the core module imported and wlib added to specialArgs

wlib.evalModules takes the same arguments as nixpkgs.lib.evalModules

wlib.evalModule

evalModule = module: wlib.evalModules { modules = [ module ]; };

Evaluates the module along with the core options, using lib.evalModules

Takes a module as its argument. Returns the result from lib.evalModules directly.

To submit a module to this repo, this function must be able to evaluate it.

The wrapper module system integrates with NixOS module evaluation:

• Uses lib.evalModules for configuration evaluation
• Supports all standard module features (imports, conditionals, mkIf, etc.)
• Provides config for accessing evaluated configuration
• Provides options for introspection and documentation

wlib.wrapModule

Creates a reusable wrapper module.

Imports wlib.modules.default then evaluates the module. It then returns .config so that .wrap is easily accessible!

Use this when you want to quickly create a wrapper but without providing it a pkgs yet.

Equivalent to:

wrapModule = (wlib.evalModule wlib.modules.default).config.apply;

Example usage:

  helloWrapper = wrapModule ({ config, wlib, ... }: {
    options.greeting = lib.mkOption {
      type = lib.types.str;
      default = "hello";
    };
    config.package = config.pkgs.hello;
    config.flags = {
      "--greeting" = config.greeting;
    };
  };

  # This will return a derivation that wraps the hello package with the --greeting flag set to "hi".
  helloWrapper.wrap {
    pkgs = pkgs;
    greeting = "hi";
  };

wlib.wrapPackage

Imports wlib.modules.default then evaluates the module. It then returns the wrapped package.

Use this when you want to quickly create a wrapped package directly. Requires a pkgs to be set.

Equivalent to:

wrapModule = (wlib.evalModule wlib.modules.default).config.wrap;

wlib.mkOutOfStoreSymlink

mkOutOfStoreSymlink :: pkgs -> path -> { out = ...; ... }

Lifted straight from home manager, but requires pkgs to be passed to it first.

Creates a symlink to a local absolute path, does not check if it is a store path first.

Returns a store path that can be used for things which require a store path.

wlib.getPackageOutputsSet

getPackageOutputsSet :: Derivation -> AttrSet

Given a package derivation, returns an attribute set mapping each of its output names (e.g. "out", "dev", "doc") to the corresponding output path.

This is useful when a wrapper or module needs to reference multiple outputs of a single derivation. If the derivation does not define multiple outputs, an empty set is returned.

Example: getPackageOutputsSet pkgs.git => { out = /nix/store/...-git; man = /nix/store/...-git-man; }

wlib.escapeShellArgWithEnv

Escape a shell argument while preserving environment variable expansion.

This escapes backslashes and double quotes to prevent injection, then

wraps the result in double quotes.

Unlike lib.escapeShellArg which uses single quotes, this allows

environment variable expansion (e.g., $HOME, ${VAR}).

Caution! This is used by wlib.modules.makeWrapperNix to escape things, but the wlib.modules.makeWrapper implementation passes its args to pkgs.makeWrapper at build time, so it may not always do what you expect!

Example

escapeShellArgWithEnv "$HOME/config.txt"

=> "\"$HOME/config.txt\""

escapeShellArgWithEnv "/path/with\"quote"

=> "\"/path/with\\\"quote\""

escapeShellArgWithEnv "/path/with\\backslash"

=> "\"/path/with\\\\backslash\""