[Python-checkins] cpython (merge 3.5 -> default): Merge

[raymond.hettinger]

https://hg.python.org/cpython/rev/e0df94327586
changeset:   100438:e0df94327586
parent:      100435:eb120f50df4a
parent:      100437:ab3e4be4b539
user:        Raymond Hettinger <python at rcn.com>
date:        Sun Mar 06 18:12:08 2016 -0800
summary:
  Merge

files:
  Doc/library/itertools.rst  |  5 +++++
  Lib/test/test_itertools.py |  8 ++++++++
  2 files changed, 13 insertions(+), 0 deletions(-)


diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -693,6 +693,11 @@
        "Returns the nth item or a default value"
        return next(islice(iterable, n, None), default)
 
+   def all_equal(iterable):
+       "Returns True if all the elements are equal to each other"
+       g = groupby(iterable)
+       return next(g, True) and not next(g, False)
+
    def quantify(iterable, pred=bool):
        "Count how many times the predicate is true"
        return sum(map(pred, iterable))
diff --git a/Lib/test/test_itertools.py b/Lib/test/test_itertools.py
--- a/Lib/test/test_itertools.py
+++ b/Lib/test/test_itertools.py
@@ -2064,6 +2064,11 @@
 ...     "Returns the nth item or a default value"
 ...     return next(islice(iterable, n, None), default)
 
+>>> def all_equal(iterable):
+...     "Returns True if all the elements are equal to each other"
+...     g = groupby(iterable)
+...     return next(g, True) and not next(g, False)
+
 >>> def quantify(iterable, pred=bool):
 ...     "Count how many times the predicate is true"
 ...     return sum(map(pred, iterable))
@@ -2177,6 +2182,9 @@
 >>> nth('abcde', 9) is None
 True
 
+>>> [all_equal(s) for s in ('', 'A', 'AAAA', 'AAAB', 'AAABA')]
+[True, True, True, False, False]
+
 >>> quantify(range(99), lambda x: x%2==0)
 50
 

-- 
Repository URL: https://hg.python.org/cpython