Type Objects

PyTypeObject

The C structure of the objects used to describe built-in types.

PyObject* PyType_Type

This is the type object for type objects; it is the same object as type in the Python layer.

int PyType_Check(PyObject *o)

Return true if the object o is a type object, including instances of types derived from the standard type object. Return false in all other cases.

int PyType_CheckExact(PyObject *o)

Return true if the object o is a type object, but not a subtype of the standard type object. Return false in all other cases.

unsigned int PyType_ClearCache()

Clear the internal lookup cache. Return the current version tag.

unsigned long PyType_GetFlags(PyTypeObject* type)

Return the tp_flags member of type. This function is primarily meant for use with Py_LIMITED_API; the individual flag bits are guaranteed to be stable across Python releases, but access to tp_flags itself is not part of the limited API.

New in version 3.2.

Changed in version 3.4: The return type is now unsigned long rather than long.

void PyType_Modified(PyTypeObject *type)

Invalidate the internal lookup cache for the type and all of its subtypes. This function must be called after any manual modification of the attributes or base classes of the type.

int PyType_HasFeature(PyTypeObject *o, int feature)

Return true if the type object o sets the feature feature. Type features are denoted by single bit flags.

int PyType_IS_GC(PyTypeObject *o)

Return true if the type object includes support for the cycle detector; this tests the type flag Py_TPFLAGS_HAVE_GC.

int PyType_IsSubtype(PyTypeObject *a, PyTypeObject *b)

Return true if a is a subtype of b.

This function only checks for actual subtypes, which means that __subclasscheck__() is not called on b. Call PyObject_IsSubclass() to do the same check that issubclass() would do.

PyObject* PyType_GenericAlloc(PyTypeObject *type, Py_ssize_t nitems)

Return value: New reference.

Generic handler for the tp_alloc slot of a type object. Use Python’s default memory allocation mechanism to allocate a new instance and initialize all its contents to NULL.

PyObject* PyType_GenericNew(PyTypeObject *type, PyObject *args, PyObject *kwds)

Return value: New reference.

Generic handler for the tp_new slot of a type object. Create a new instance using the type’s tp_alloc slot.

int PyType_Ready(PyTypeObject *type)

Finalize a type object. This should be called on all type objects to finish their initialization. This function is responsible for adding inherited slots from a type’s base class. Return 0 on success, or return -1 and sets an exception on error.

PyObject* PyType_FromSpec(PyType_Spec *spec)

Creates and returns a heap type object from the spec passed to the function.

PyObject* PyType_FromSpecWithBases(PyType_Spec *spec, PyObject *bases)

Creates and returns a heap type object from the spec. In addition to that, the created heap type contains all types contained by the bases tuple as base types. This allows the caller to reference other heap types as base types.

New in version 3.3.

void* PyType_GetSlot(PyTypeObject *type, int slot)

Return the function pointer stored in the given slot. If the result is NULL, this indicates that either the slot is NULL, or that the function was called with invalid parameters. Callers will typically cast the result pointer into the appropriate function type.

New in version 3.4.