Merged revisions 82766 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

Since 'purge' is an API change, modified it to be _purge for 3.1
and deleted the doc update.

........
  r82766 | r.david.murray | 2010-07-10 09:52:13 -0400 (Sat, 10 Jul 2010) | 5 lines

  Fix 'refleak' introduced by fnmatch cache purge tests.

  This introduces a 'purge' function for the fnmatch module analogous
  to the 'purge' function in the re module.
........
diff --git a/Lib/fnmatch.py b/Lib/fnmatch.py
index 26ae4cc..be1fd1d 100644
--- a/Lib/fnmatch.py
+++ b/Lib/fnmatch.py
@@ -12,12 +12,17 @@
 
 import re
 
-__all__ = ["filter", "fnmatch","fnmatchcase","translate"]
+__all__ = ["filter", "fnmatch", "fnmatchcase", "translate"]
 
 _cache = {}  # Maps text patterns to compiled regexen.
 _cacheb = {}  # Ditto for bytes patterns.
 _MAXCACHE = 100 # Maximum size of caches
 
+def _purge():
+    """Clear the pattern cache"""
+    _cache.clear()
+    _cacheb.clear()
+
 def fnmatch(name, pat):
     """Test whether FILENAME matches PATTERN.