It is sometimes desired to perform an action over the loaded version of a module (for instance to display its content). Using the bare module name, for instance foo when foo/1.0 is loaded, will not work as this name designates the default version of the module, which for instance is foo/2.0 not our loaded version foo/1.0.
Adding a new symbolic version to the advanced version specifiers named loaded, would do the trick: module display foo@loaded will automatically resolve to the version of foo which is currently loaded.