[Python-checkins] r86401 - python/branches/release31-maint/Doc/library/difflib.rst

[terry.reedy]

Author: terry.reedy
Date: Wed Nov 10 18:50:26 2010
New Revision: 86401

Log:
Issue 2986: document heuristic for 3.1

Modified:
   python/branches/release31-maint/Doc/library/difflib.rst

Modified: python/branches/release31-maint/Doc/library/difflib.rst
==============================================================================
--- python/branches/release31-maint/Doc/library/difflib.rst	(original)
+++ python/branches/release31-maint/Doc/library/difflib.rst	Wed Nov 10 18:50:26 2010
@@ -35,6 +35,11 @@
    complicated way on how many elements the sequences have in common; best case
    time is linear.
 
+   **Heuristic:** To speed-up matching, items whose duplicates appear more than 1% of
+   the time in sequences of at least 200 items are treated as junk.  This has the
+   unfortunate side-effect of giving bad results for sequences constructed from
+   a small set of items.  An option to turn off the heuristic will be added to
+   Python 3.2.
 
 .. class:: Differ