diff --git a/Doc/c-api/descriptor.rst b/Doc/c-api/descriptor.rst index e23288c6a58590..b913e24b3c7cc8 100644 --- a/Doc/c-api/descriptor.rst +++ b/Doc/c-api/descriptor.rst @@ -8,13 +8,31 @@ Descriptor Objects "Descriptors" are objects that describe some attribute of an object. They are found in the dictionary of type objects. -.. XXX document these! - .. c:function:: PyObject* PyDescr_NewGetSet(PyTypeObject *type, struct PyGetSetDef *getset) + Create a new get-set descriptor for extension type *type* from the + :c:type:`PyGetSetDef` structure *getset*. + + Get-set descriptors expose attributes implemented by C getter and setter + functions rather than stored directly in the instance. This is the same kind + of descriptor created for entries in :c:member:`~PyTypeObject.tp_getset`, and + it appears in Python as a :class:`types.GetSetDescriptorType` object. + + On success, return a :term:`strong reference` to the descriptor. Return + ``NULL`` with an exception set on failure. + +.. c:function:: PyObject* PyDescr_NewMember(PyTypeObject *type, struct PyMemberDef *member) -.. c:function:: PyObject* PyDescr_NewMember(PyTypeObject *type, struct PyMemberDef *meth) + Create a new member descriptor for extension type *type* from the + :c:type:`PyMemberDef` structure *member*. + Member descriptors expose fields in the type's C struct as Python + attributes. This is the same kind of descriptor created for entries in + :c:member:`~PyTypeObject.tp_members`, and it appears in Python as a + :class:`types.MemberDescriptorType` object. + + On success, return a :term:`strong reference` to the descriptor. Return + ``NULL`` with an exception set on failure. .. c:var:: PyTypeObject PyMemberDescr_Type @@ -30,22 +48,53 @@ found in the dictionary of type objects. The type object for get/set descriptor objects created from :c:type:`PyGetSetDef` structures. These descriptors implement attributes whose value is computed by C getter and setter functions, and are used - for many built-in type attributes. + for many built-in type attributes. They correspond to + :class:`types.GetSetDescriptorType` objects in Python. .. c:function:: PyObject* PyDescr_NewMethod(PyTypeObject *type, struct PyMethodDef *meth) + Create a new method descriptor for extension type *type* from the + :c:type:`PyMethodDef` structure *meth*. + + Method descriptors expose C functions as methods on a type. This is the same + kind of descriptor created for entries in + :c:member:`~PyTypeObject.tp_methods`, and it appears in Python as a + :class:`types.MethodDescriptorType` object. + + On success, return a :term:`strong reference` to the descriptor. Return + ``NULL`` with an exception set on failure. .. c:var:: PyTypeObject PyMethodDescr_Type The type object for method descriptor objects created from :c:type:`PyMethodDef` structures. These descriptors expose C functions as - methods on a type, and correspond to :class:`types.MemberDescriptorType` + methods on a type, and correspond to :class:`types.MethodDescriptorType` objects in Python. -.. c:function:: PyObject* PyDescr_NewWrapper(PyTypeObject *type, struct wrapperbase *wrapper, void *wrapped) +.. c:struct:: wrapperbase + + Describes a slot wrapper used by :c:func:`PyDescr_NewWrapper`. + Each ``wrapperbase`` record stores the Python-visible name and metadata for a + special method implemented by a type slot, together with the wrapper + function used to adapt that slot to Python's calling convention. + +.. c:function:: PyObject* PyDescr_NewWrapper(PyTypeObject *type, struct wrapperbase *base, void *wrapped) + + Create a new wrapper descriptor for extension type *type* from the + :c:struct:`wrapperbase` structure *base* and the wrapped slot function + pointer + *wrapped*. + + Wrapper descriptors expose special methods implemented by type slots. This + is the same kind of descriptor that CPython creates for slot-based special + methods such as ``__repr__`` or ``__add__``, and it appears in Python as a + :class:`types.WrapperDescriptorType` object. + + On success, return a :term:`strong reference` to the descriptor. Return + ``NULL`` with an exception set on failure. .. c:var:: PyTypeObject PyWrapperDescr_Type @@ -58,6 +107,16 @@ found in the dictionary of type objects. .. c:function:: PyObject* PyDescr_NewClassMethod(PyTypeObject *type, PyMethodDef *method) + Create a new class method descriptor for extension type *type* from the + :c:type:`PyMethodDef` structure *method*. + + Class method descriptors expose C methods that receive the class rather than + an instance when accessed. This is the same kind of descriptor created for + ``METH_CLASS`` entries in :c:member:`~PyTypeObject.tp_methods`, and it + appears in Python as a :class:`types.ClassMethodDescriptorType` object. + + On success, return a :term:`strong reference` to the descriptor. Return + ``NULL`` with an exception set on failure. .. c:function:: int PyDescr_IsData(PyObject *descr) @@ -66,8 +125,18 @@ found in the dictionary of type objects. no error checking. -.. c:function:: PyObject* PyWrapper_New(PyObject *, PyObject *) +.. c:function:: PyObject* PyWrapper_New(PyObject *d, PyObject *self) + + Create a new bound wrapper object from the wrapper descriptor *d* and the + instance *self*. + + This is the bound form of a wrapper descriptor created by + :c:func:`PyDescr_NewWrapper`. CPython creates these objects when a slot + wrapper is accessed through an instance, and they appear in Python as + :class:`types.MethodWrapperType` objects. + On success, return a :term:`strong reference` to the wrapper object. Return + ``NULL`` with an exception set on failure. .. c:macro:: PyDescr_COMMON @@ -104,9 +173,9 @@ Built-in descriptors .. c:var:: PyTypeObject PyClassMethodDescr_Type The type object for C-level class method descriptor objects. - This is the type of the descriptors created for :func:`classmethod` defined in - C extension types, and is the same object as :class:`classmethod` - in Python. + This is the type of the descriptors created for :func:`classmethod` defined + in C extension types, and corresponds to + :class:`types.ClassMethodDescriptorType` objects in Python. .. c:function:: PyObject *PyClassMethod_New(PyObject *callable) diff --git a/Doc/tools/.nitignore b/Doc/tools/.nitignore index ffe98d332d6e93..189173a5f8a75f 100644 --- a/Doc/tools/.nitignore +++ b/Doc/tools/.nitignore @@ -2,7 +2,6 @@ # as tested on the CI via check-warnings.py in reusable-docs.yml. # Keep lines sorted lexicographically to help avoid merge conflicts. -Doc/c-api/descriptor.rst Doc/c-api/init_config.rst Doc/c-api/intro.rst Doc/c-api/stable.rst