Pierre-Yves David <pierre-yves.david@octobus.net> [Fri, 16 Jun 2017 16:50:11 +0200] rev 2606
obsfate: improve prune support in _successorsetverb
In the prune case, still have markers (at least the prune markers). If we want
to be able to return these markers we need the underlying function to support
it.