diff -r 8d572bf526e6 Doc/library/itertools.rst
--- a/Doc/library/itertools.rst	Sun Jan 26 21:35:22 2014 -0500
+++ b/Doc/library/itertools.rst	Mon Jan 27 15:31:38 2014 +0800
@@ -525,7 +525,8 @@
 .. function:: repeat(object[, times])
 
    Make an iterator that returns *object* over and over again. Runs indefinitely
-   unless the *times* argument is specified. Used as argument to :func:`map` for
+   unless the *times* argument is specified and is not ``None``.  Negative
+   *times* means zero repetitions.  Used as argument to :func:`map` for
    invariant parameters to the called function.  Also used with :func:`zip` to
    create an invariant part of a tuple record.  Equivalent to::
 
diff -r 8d572bf526e6 Lib/test/test_itertools.py
--- a/Lib/test/test_itertools.py	Sun Jan 26 21:35:22 2014 -0500
+++ b/Lib/test/test_itertools.py	Mon Jan 27 15:31:38 2014 +0800
@@ -949,7 +949,11 @@
         self.assertEqual(list(repeat('a', 3)), ['a', 'a', 'a'])
         self.assertEqual(take(3, repeat('a')), ['a', 'a', 'a'])
         self.assertEqual(list(repeat('a', 0)), [])
+        self.assertEqual(list(repeat('a', -1)), [])
         self.assertEqual(list(repeat('a', -3)), [])
+        self.assertEqual(list(repeat(object='a', times=0)), [])
+        self.assertEqual(list(repeat(object='a', times=-1)), [])
+        self.assertEqual(list(repeat(object='a', times=-3)), [])
         self.assertRaises(TypeError, repeat)
         self.assertRaises(TypeError, repeat, None, 3, 4)
         self.assertRaises(TypeError, repeat, None, 'a')
@@ -960,6 +964,11 @@
         list(r)
         self.assertEqual(repr(r), 'repeat((1+0j), 0)')
 
+        # None value for times represents endless repetitions
+        self.assertEqual(repr(repeat('a')), "repeat('a')")
+        self.assertEqual(repr(repeat('a', None)), "repeat('a')")
+        self.assertEqual(repr(repeat('a', times=None)), "repeat('a')")
+
         # check copy, deepcopy, pickle
         c = repeat(object='a', times=10)
         self.assertEqual(next(c), 'a')
diff -r 8d572bf526e6 Modules/itertoolsmodule.c
--- a/Modules/itertoolsmodule.c	Sun Jan 26 21:35:22 2014 -0500
+++ b/Modules/itertoolsmodule.c	Mon Jan 27 15:31:38 2014 +0800
@@ -4090,15 +4090,27 @@
 {
     repeatobject *ro;
     PyObject *element;
+    PyObject *count_object = Py_None;
     Py_ssize_t cnt = -1;
     static char *kwargs[] = {"object", "times", NULL};
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|n:repeat", kwargs,
-                                     &element, &cnt))
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|O:repeat", kwargs,
+                                     &element, &count_object))
         return NULL;
 
-    if (PyTuple_Size(args) == 2 && cnt < 0)
-        cnt = 0;
+    if (count_object == Py_None)
+        cnt = -1;
+    else {
+        cnt = PyLong_AsSsize_t(count_object);
+        if ((cnt == -1) && PyErr_Occurred()) {
+            if (PyErr_ExceptionMatches(PyExc_TypeError))
+                PyErr_SetString(PyExc_TypeError,
+                                "times must be integer or None");
+            return NULL;
+        }
+        if (cnt < 0)
+            cnt = 0;
+    }
 
     ro = (repeatobject *)type->tp_alloc(type, 0);
     if (ro == NULL)
@@ -4175,9 +4187,9 @@
 };
 
 PyDoc_STRVAR(repeat_doc,
-"repeat(object [,times]) -> create an iterator which returns the object\n\
-for the specified number of times.  If not specified, returns the object\n\
-endlessly.");
+"repeat(object, times=None) -> create an iterator which returns the object\n\
+for the specified number of times.  If times is not specified or None,\n\
+returns the object endlessly.  Negative times means zero repetitions.");
 
 static PyTypeObject repeat_type = {
     PyVarObject_HEAD_INIT(NULL, 0)