bpo-38140: Document offsets in PyMemberDef by encukou · Pull Request #16354 · python/cpython

python

@@ -346,6 +346,19 @@ Accessing attributes of extension types Only :c:macro:`T_OBJECT` and :c:macro:`T_OBJECT_EX` members can be deleted. (They are set to *NULL*).
.. _pymemberdef-offsets:
Heap allocated types (created using :c:func:`PyType_FromSpec` or similar), ``PyMemberDef`` may contain defintitions for the special members ``__dictoffset__`` and ``__weaklistoffset__``, corresponding to :c:member:`~PyTypeObject.tp_dictoffset` and :c:member:`~PyTypeObject.tp_weaklistoffset` in type objects. These must be defined with ``T_PYSSIZET`` and ``READONLY``, for example::
static PyMemberDef spam_type_members[] = { {"__dictoffset__", T_PYSSIZET, offsetof(Spam_object, dict), READONLY}, {NULL} /* Sentinel */ };
.. c:type:: PyGetSetDef