--- a/hgext/evolve.py	Fri Feb 07 09:36:42 2014 +0100
+++ b/hgext/evolve.py	Tue Feb 11 00:02:18 2014 -0600
@@ -1387,6 +1387,7 @@
     [('n', 'new', [], _("successor changeset (DEPRECATED)")),
      ('s', 'succ', [], _("successor changeset")),
      ('r', 'rev', [], _("revisions to prune")),
+     ('', 'biject', False, _("do a 1-1 map between rev and successor ranges")),
      ('B', 'bookmark', '', _("remove revs only reachable from given"
                              " bookmark"))] + metadataopts,
     _('[OPTION] [-r] REV...'))
@@ -1402,13 +1403,19 @@
     When the working directory parent is pruned the repository is updated to a
     non obsolete parents.
 
-    you can use the ``--succ`` option to informs mercurial that a newer version
+    You can use the ``--succ`` option to informs mercurial that a newer version
     of the pruned changeset exists.
+
+    You can use the ``--biject`` option to specify a 1-1 (bijection) between
+    revisions to prune and successor changesets. This option may be removed in
+    a future release (with the functionality absored automatically).
+
     """
     revs = set(scmutil.revrange(repo, list(revs) + opts.get('rev')))
     succs = opts['new'] + opts['succ']
     bookmark = opts.get('bookmark')
     metadata = _getmetadata(**opts)
+    biject = opts.get('biject')
 
     if bookmark:
         marks,revs = _reachablefrombookmark(repo, revs, bookmark)
@@ -1438,11 +1445,20 @@
 
         # defines successors changesets
         sucs = tuple(repo[n] for n in sortedrevs(succs))
-        if len(sucs) > 1 and len(precs) > 1:
+        if not biject and len(sucs) > 1 and len(precs) > 1:
             msg = "Can't use multiple successors for multiple precursors"
             raise util.Abort(msg)
+
+        if biject and len(sucs) != len(precs):
+            msg = "Can't use %d successors for %d precursors" % (len(sucs), len(precs))
+            raise util.Abort(msg)
+
+        relations = [(p, sucs) for p in precs]
+        if biject:
+            relations = [(p, (s,)) for p, s in zip(precs, sucs)]
+
         # create markers
-        createmarkers(repo, [(p, sucs) for p in precs], metadata=metadata)
+        createmarkers(repo, relations, metadata=metadata)
 
         # informs that changeset have been pruned
         ui.status(_('%i changesets pruned\n') % len(precs))