From: Andrew Kuchling <amk@amk.ca>
Date: Wed, 16 Apr 2014 02:28:40 +0000 (-0400)
Subject: #20103: Rewrite description of itertools.accumulate().
X-Git-Tag: v3.5.0a1~1855
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=15b04eb42902f84fa3e35387b0c7c3391a204f65;p=thirdparty%2FPython%2Fcpython.git

#20103: Rewrite description of itertools.accumulate().

Patch by Christian Hudon.
---

diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
index f489535c5361..1f0bcedc0a4e 100644
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -87,10 +87,15 @@ loops that truncate the stream.
 
 .. function:: accumulate(iterable[, func])
 
-    Make an iterator that returns accumulated sums. Elements may be any addable
-    type including :class:`~decimal.Decimal` or :class:`~fractions.Fraction`.
-    If the optional *func* argument is supplied, it should be a function of two
-    arguments and it will be used instead of addition.
+    Make an iterator that returns accumulated sums, or accumulated
+    results of other binary functions (specified via the optional
+    *func* argument).  If *func* is supplied, it should be a function
+    of two arguments. Elements of the input *iterable* may be any type
+    that can be accepted as arguments to *func*. (For example, with
+    the default operation of addition, elements may be any addable
+    type including :class:`~decimal.Decimal` or
+    :class:`~fractions.Fraction`.) If the input iterable is empty, the
+    output iterable will also be empty.
 
     Equivalent to::