>>> merge such a change, as the 3.x plugin API is released and should
>>> not be broken. I will thus keep the existing `renamepage` as it
>>> is, and call `rename` the global hook I need. --[[intrigeri]]
+
+>>>> Done in my `po` branch. --[[intrigeri]]
+
+I think I see a problem in the rename hook. The hook is called
+before the plugin adds any subpages to the set of pages to rename.
+So, if the user choses to rename subpages, po will not notice
+they are moving, and will not move their po files.
+
+Perhaps the hooks should be moved to come after subpages are added.
+This would, though, mean that if the hook somehow decides to add
+entirely other pages to the list, their subpages would not be
+automatically added.
+
+I also have some qualms about the design of the hook. In particular,
+passing the mutable array reference probably makes it impossible
+to use from external plugins. Instead it could return any additional
+rename hashes it wants to add. Or, if the ability to modify existing
+hashes is desired, it could return the full set of hashes.
+
+--[[Joey]]
+
+> I fixed the last part, i.e. a rename hook function now returns the
+> full set of hashes. As I also converted it to take named parameters,
+> such a function still is passed a reference to the original array,
+> though, because one can't build a hash containing an array of hashes
+> as a value, without passing this array as a reference.
+>
+> I'm not entirely sure about your first concern. Calling the hook
+> before or after the subpages addition both have their own problems.
+>
+> What about running the hook before *and* after the subpages
+> addition, with an additional `when` named parameter, so that
+> a given hook function can choose to act only before or after, or both?
+>
+> --[[intrigeri]]