From: Raymond Hettinger <python@rcn.com>
Date: Sat, 5 Oct 2002 15:38:16 +0000 (+0000)
Subject: Backport 1.100:  Discussion of Stop Iteration in the Iterator Protocol.
X-Git-Tag: v2.2.2b1~58
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2d4b27ea36d9c98ec52d770488801e0afb6cca84;p=thirdparty%2FPython%2Fcpython.git

Backport 1.100:  Discussion of Stop Iteration in the Iterator Protocol.
---

diff --git a/Doc/lib/libstdtypes.tex b/Doc/lib/libstdtypes.tex
index 4d659e60d11f..9d15bbd9426c 100644
--- a/Doc/lib/libstdtypes.tex
+++ b/Doc/lib/libstdtypes.tex
@@ -367,6 +367,13 @@ general and specific sequence types, dictionaries, and other more
 specialized forms.  The specific types are not important beyond their
 implementation of the iterator protocol.
 
+The intention of the protocol is that once an iterator's
+\method{next()} method raises \exception{StopIteration}, it will
+continue to do so on subsequent calls.  Implementations that
+do not obey this property are deemed broken.  (This constraint
+was added in Python 2.3; in Python 2.2, various iterators are
+broken according to this rule.)
+
 
 \subsection{Sequence Types \label{typesseq}}