Hi Bastien,
I didn't follow this thread in detail. But shouldn't it be enough to symlink e.g. org-icalendar against ox-icalendar. As far as I understood emacs would prioritize those local symlinks over the system wide installation. This would be a temporary solution until a new emacs release.
Actually, under Linux, this is a pretty common way to bend dependencies towards the newest version of a lib.
Not sure for windows users.

Instead of a simple symlink, the current dev head could have wrappers for those "old" files which bend the calls to the new files and issue a warning.
That would help to identify 3 party code which needs some rework.

Torsten

Bastien <bzg@altern.org> wrote:
Hi David,

David Engster <deng@randomsample.de> writes:

Did you actually try that? How should Emacs possibly know that the file
ox-icalendar provides the feature org-icalendar? This will only work if
ox-icalendar is already loaded.

Of course, you're right.  I reverted the commit.

So the problems stay.  For third-party libraries developers,
we cannot do anything else now than to ask them to update their
code.  For the problem of Emacs autoloaded functions, org.el
provides (load "org-loaddefs.el t t
  t) which should load
the correct autoloads from the correct files...  but that's
unstable.

It seems the ox- prefix is a bad idea, you're right.
I'll think about it
again.

Thanks,