Translations:Manual:Hooks/32/en


 * no return value (or null): the hook handler has operated successfully. (Before MediaWiki 1.23, returning true was required.)
 * "some string": an error occurred; processing should stop and the error should be shown to the user
 * false: the hook handler has done all the work necessary, or replaced normal handling. This will prevent further handlers from being run, and in some cases tells the calling function to skip normal processing.