--- a/hgext/histedit.py	Mon Sep 24 15:54:45 2012 -0500
+++ b/hgext/histedit.py	Fri Sep 21 00:30:07 2012 +0200
@@ -196,6 +196,9 @@
     return files
 
 def between(repo, old, new, keep):
+    """select and validate the set of revision to edit
+
+    When keep is false, the specified set can't have children."""
     revs = [old]
     current = old
     while current != new: