https://hg.python.org/cpython/rev/5352badd200e changeset: 98444:5352badd200e user: Raymond Hettinger <python@rcn.com> date: Wed Sep 30 23:15:02 2015 -0700 summary: Add fast paths to deque_init() for the common cases files: Modules/_collectionsmodule.c | 13 ++++++++++--- 1 files changed, 10 insertions(+), 3 deletions(-) diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c --- a/Modules/_collectionsmodule.c +++ b/Modules/_collectionsmodule.c @@ -1456,8 +1456,14 @@ Py_ssize_t maxlen = -1; char *kwlist[] = {"iterable", "maxlen", 0}; - if (!PyArg_ParseTupleAndKeywords(args, kwdargs, "|OO:deque", kwlist, &iterable, &maxlenobj)) - return -1; + if (kwdargs == NULL) { + if (!PyArg_UnpackTuple(args, "deque()", 0, 2, &iterable, &maxlenobj)) + return -1; + } else { + if (!PyArg_ParseTupleAndKeywords(args, kwdargs, "|OO:deque", kwlist, + &iterable, &maxlenobj)) + return -1; + } if (maxlenobj != NULL && maxlenobj != Py_None) { maxlen = PyLong_AsSsize_t(maxlenobj); if (maxlen == -1 && PyErr_Occurred()) @@ -1468,7 +1474,8 @@ } } deque->maxlen = maxlen; - deque_clear(deque); + if (Py_SIZE(deque) > 0) + deque_clear(deque); if (iterable != NULL) { PyObject *rv = deque_extend(deque, iterable); if (rv == NULL) -- Repository URL: https://hg.python.org/cpython