For collections.deque() objects, expose the maxlen parameter as a read-only attribute.
diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
index 9532f1b..a4fdf76 100644
--- a/Modules/_collectionsmodule.c
+++ b/Modules/_collectionsmodule.c
@@ -870,6 +870,20 @@
return 0;
}
+static PyObject *
+deque_get_maxlen(dequeobject *deque)
+{
+ if (deque->maxlen == -1)
+ Py_RETURN_NONE;
+ return PyInt_FromSsize_t(deque->maxlen);
+}
+
+static PyGetSetDef deque_getset[] = {
+ {"maxlen", (getter)deque_get_maxlen, (setter)NULL,
+ "maximum size of a deque or None if unbounded"},
+ {0}
+};
+
static PySequenceMethods deque_as_sequence = {
(lenfunc)deque_len, /* sq_length */
0, /* sq_concat */
@@ -951,7 +965,7 @@
0, /* tp_iternext */
deque_methods, /* tp_methods */
0, /* tp_members */
- 0, /* tp_getset */
+ deque_getset, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */