--- a/tools.py	Sun Feb 03 23:39:27 2008 +0100
+++ b/tools.py	Mon Feb 04 19:02:42 2008 +0100
@@ -1,3 +1,22 @@
+#
+"""
+Helper functions and classes
+"""
+import re
+
+def str_num_cmp(s1,s2):
+    """
+    string comparator function that will put 'toto_10' after 'toto_2'
+    Also works for strings like 'toto_1_et_23er25'.
+    """
+    r = re.compile(r'((?<=\d)\D+|(?<=\D)\d+)')
+    r1= r.split(s1)
+    r2= r.split(s2)
+    r1=[not x.isdigit() and x or int(x) for x in r1 if x!='']
+    r2=[not x.isdigit() and x or int(x) for x in r2 if x!='']
+    return cmp(r1,r2)
+
+
 class AbstractRegister(object):
     _instance = None
     _registered_type = None