User:Robmoen/Extension review/SubpageSortkey

$wgNamespacesWithSubpages[NS_MAIN] = true; in order to bypass the exit and see the new sort keys on my test category.
 * It seems as if there is some confusion about whether this is to be deployed into MW core or as an extension on wikibooks.
 * 1) The (bug:22911) request calls for this to be deployed as an extension on wikibooks.
 * Is there a specific reason why the onGetDefaultSortkey hook exits if there are no subpages for the current page namespace ?
 * 1) Perhaps this is local config problem on my end. In my LocalSettings.php, I had to enable subpages in the main namespace
 * Per the bug report and documentation this extension seems to be functioning as described. I do not see any blockers for deployment.