# HG changeset patch
# User Matt Mackall <mpm@selenic.com>
# Date 2006-11-19 22:32:36
# Node ID b0fd43effdb34c7debddefbca3c9d178f2df83d9
# Parent  20912eb2667de45415eff601bfc045ae0fe8db42

add docstring to reachable

diff --git a/mercurial/revlog.py b/mercurial/revlog.py
--- a/mercurial/revlog.py
+++ b/mercurial/revlog.py
@@ -543,6 +543,8 @@ class revlog(object):
             return self.index[rev][-5]
 
     def reachable(self, node, stop=None):
+        """return a hash of all nodes ancestral to a given node, including
+         the node itself, stopping when stop is matched"""
         reachable = {}
         visit = [node]
         reachable[node] = 1