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Include/internal/pycore_descrobject.h

cpython 3.14 @ ab2d84fe1023/Include/internal/pycore_descrobject.h

pycore_descrobject.h is the internal companion to Include/descrobject.h and Include/cpython/descrobject.h. The public headers declare the four descriptor structs (PyMethodDescrObject, PyMemberDescrObject, PyGetSetDescrObject, PyWrapperDescrObject) and the PyDescr_COMMON macro that embeds PyDescrObject (holding d_type, d_name, d_qualname) at the top of each one. The internal header adds two things the public API does not expose: the full layout of propertyobject (the C backing of the built-in property type) and the extern declaration for _PyMethodWrapper_Type.

propertyobject holds all five attributes that make up a Python property: prop_get, prop_set, prop_del, prop_doc, and prop_name, plus the getter_doc flag that records whether the docstring was inherited from the getter. Build-core code (the type machinery, super, and the optimizer) reads these fields directly rather than going through the Python-level attribute protocol. _PyMethodWrapper_Type is the C type for the bound-method wrapper objects returned when you access a slot wrapper on an instance (for example, (1).__add__). It is exported so that Objects/typeobject.c and the _testcapi extension can reference it without declaring it themselves.

Map​

LinesSymbolRolegopy
11-19propertyobjectFull C layout of built-in property: get/set/del/doc/name callables plus getter_doc flagobjects/property.go
21_PyPropertyObjectTypedef alias for propertyobject used internallyobjects/property.go
23_PyMethodWrapper_TypeExtern PyTypeObject for bound slot-wrapper objects (method-wrapper)objects/method.go
26-31PyDescrObject (in cpython/descrobject.h)Base descriptor layout: d_type, d_name, d_qualname; embedded via PyDescr_COMMONobjects/descr.go
38-58Four descriptor structs (in cpython/descrobject.h)PyMethodDescrObject, PyMemberDescrObject, PyGetSetDescrObject, PyWrapperDescrObjectobjects/descr.go

Reading​

Guard and build-core requirement​

Lines 1-9 apply the standard Py_BUILD_CORE guard. This header is never included by extension code. Any file that includes it must define Py_BUILD_CORE first, which limits its users to the interpreter core, the Modules/_testcapi family, and the JIT.

propertyobject layout​

The struct at lines 11-19 gives build-core code direct field access to all five callable slots of a property plus the getter_doc integer flag. The getter_doc flag is 1 when the property docstring was copied from the getter function rather than supplied explicitly; type.__new__ uses this to decide whether a subclass should inherit the doc from a redefined getter.

_PyPropertyObject alias​

The typedef propertyobject _PyPropertyObject at line 21 lets newer internal code use the _Py-prefixed name consistently without a rename. Both names refer to the same struct; the alias is the preferred spelling in new code added after Python 3.12.

_PyMethodWrapper_Type export​

Line 23 is a single extern that makes the method-wrapper type object available across translation units. Method-wrapper instances are created by Objects/descrobject.c:wrapperdescr_get whenever a slot-wrapper descriptor is accessed on an instance. The type object itself lives in that file, and the extern here lets typeobject.c, abstract.c, and test extensions reference it without a forward declaration in every file.

// Include/internal/pycore_descrobject.h (lines 11-23)
typedef struct {
    PyObject_HEAD
    PyObject *prop_get;
    PyObject *prop_set;
    PyObject *prop_del;
    PyObject *prop_doc;
    PyObject *prop_name;
    int getter_doc;
} propertyobject;

typedef propertyobject _PyPropertyObject;

extern PyTypeObject _PyMethodWrapper_Type;

gopy mirror​

Not yet ported.