bpo-37004: Documented asymmetry of string arguments in difflib.SequenceMatcher for ratio method (GH-13482) (#15157)
https://bugs.python.org/issue37004
(cherry picked from commit e9cbcd0018abd2a5f2348c45d5c9c4265c4f42dc)
Co-authored-by: sweeneyde <36520290+sweeneyde@users.noreply.github.com>
diff --git a/Doc/library/difflib.rst b/Doc/library/difflib.rst
index f044cb2..e245ab8 100644
--- a/Doc/library/difflib.rst
+++ b/Doc/library/difflib.rst
@@ -543,6 +543,16 @@
to try :meth:`quick_ratio` or :meth:`real_quick_ratio` first to get an
upper bound.
+ .. note::
+
+ Caution: The result of a :meth:`ratio` call may depend on the order of
+ the arguments. For instance::
+
+ >>> SequenceMatcher(None, 'tide', 'diet').ratio()
+ 0.25
+ >>> SequenceMatcher(None, 'diet', 'tide').ratio()
+ 0.5
+
.. method:: quick_ratio()