So you can now do things like: $ nix-env -qa '.*zip.*' $ nix-env -qa '.*(firefox|chromium).*'
That is, you don't need to pass '*' anymore, so nix-env -qa is equivalent to nix-env -qa '*'
logic through the `parseDrvName' and `compareVersions' primops. This will allow expressions to easily check whether some dependency is a specific needed version or falls in some version range. See tests/lang/eval-okay-versions.nix for examples.