Type Objects¶
- typePyTypeObject¶
- Part of theLimited API (as an opaque struct).
The C structure of the objects used to describe built-in types.
- PyTypeObjectPyType_Type¶
- Part of theStable ABI.
This is the type object for type objects; it is the same object as
typein the Python layer.
- intPyType_Check(PyObject*o)¶
Return non-zero if the objecto is a type object, including instances oftypes derived from the standard type object. Return 0 in all other cases.This function always succeeds.
- intPyType_CheckExact(PyObject*o)¶
Return non-zero if the objecto is a type object, but not a subtype ofthe standard type object. Return 0 in all other cases. This functionalways succeeds.
- unsignedintPyType_ClearCache()¶
- Part of theStable ABI.
Clear the internal lookup cache. Return the current version tag.
- unsignedlongPyType_GetFlags(PyTypeObject*type)¶
- Part of theStable ABI.
Return the
tp_flagsmember oftype. This function is primarilymeant for use withPy_LIMITED_API; the individual flag bits areguaranteed to be stable across Python releases, but access totp_flagsitself is not part of thelimited API.New in version 3.2.
Changed in version 3.4:The return type is now
unsignedlongrather thanlong.
- voidPyType_Modified(PyTypeObject*type)¶
- Part of theStable ABI.
Invalidate the internal lookup cache for the type and all of itssubtypes. This function must be called after any manualmodification of the attributes or base classes of the type.
- intPyType_HasFeature(PyTypeObject*o,intfeature)¶
Return non-zero if the type objecto sets the featurefeature.Type features are denoted by single bit flags.
- intPyType_IS_GC(PyTypeObject*o)¶
Return true if the type object includes support for the cycle detector; thistests the type flag
Py_TPFLAGS_HAVE_GC.
- intPyType_IsSubtype(PyTypeObject*a,PyTypeObject*b)¶
- Part of theStable ABI.
Return true ifa is a subtype ofb.
This function only checks for actual subtypes, which means that
__subclasscheck__()is not called onb. CallPyObject_IsSubclass()to do the same check thatissubclass()would do.
- PyObject*PyType_GenericAlloc(PyTypeObject*type,Py_ssize_tnitems)¶
- Return value: New reference. Part of theStable ABI.
Generic handler for the
tp_allocslot of a type object. UsePython’s default memory allocation mechanism to allocate a new instance andinitialize all its contents toNULL.
- PyObject*PyType_GenericNew(PyTypeObject*type,PyObject*args,PyObject*kwds)¶
- Return value: New reference. Part of theStable ABI.
Generic handler for the
tp_newslot of a type object. Create anew instance using the type’stp_allocslot.
- intPyType_Ready(PyTypeObject*type)¶
- Part of theStable ABI.
Finalize a type object. This should be called on all type objects to finishtheir initialization. This function is responsible for adding inherited slotsfrom a type’s base class. Return
0on success, or return-1and sets anexception on error.Note
If some of the base classes implements the GC protocol and the providedtype does not include the
Py_TPFLAGS_HAVE_GCin its flags, thenthe GC protocol will be automatically implemented from its parents. Onthe contrary, if the type being created does includePy_TPFLAGS_HAVE_GCin its flags then itmust implement theGC protocol itself by at least implementing thetp_traversehandle.
- PyObject*PyType_GetName(PyTypeObject*type)¶
- Return value: New reference. Part of theStable ABI since version 3.11.
Return the type’s name. Equivalent to getting the type’s
__name__attribute.New in version 3.11.
- PyObject*PyType_GetQualName(PyTypeObject*type)¶
- Return value: New reference. Part of theStable ABI since version 3.11.
Return the type’s qualified name. Equivalent to getting thetype’s
__qualname__attribute.New in version 3.11.
- void*PyType_GetSlot(PyTypeObject*type,intslot)¶
- Part of theStable ABI since version 3.4.
Return the function pointer stored in the given slot. If theresult is
NULL, this indicates that either the slot isNULL,or that the function was called with invalid parameters.Callers will typically cast the result pointer into the appropriatefunction type.See
PyType_Slot.slotfor possible values of theslot argument.New in version 3.4.
Changed in version 3.10:
PyType_GetSlot()can now accept all types.Previously, it was limited toheap types.
- PyObject*PyType_GetModule(PyTypeObject*type)¶
- Part of theStable ABI since version 3.10.
Return the module object associated with the given type when the type wascreated using
PyType_FromModuleAndSpec().If no module is associated with the given type, sets
TypeErrorand returnsNULL.This function is usually used to get the module in which a method is defined.Note that in such a method,
PyType_GetModule(Py_TYPE(self))may not return the intended result.Py_TYPE(self)may be asubclass of the intended class, and subclassesare not necessarily defined in the same module as their superclass.SeePyCMethodto get the class that defines the method.SeePyType_GetModuleByDef()for cases whenPyCMethodcannotbe used.New in version 3.9.
- void*PyType_GetModuleState(PyTypeObject*type)¶
- Part of theStable ABI since version 3.10.
Return the state of the module object associated with the given type.This is a shortcut for calling
PyModule_GetState()on the resultofPyType_GetModule().If no module is associated with the given type, sets
TypeErrorand returnsNULL.If thetype has an associated module but its state is
NULL,returnsNULLwithout setting an exception.New in version 3.9.
- PyObject*PyType_GetModuleByDef(PyTypeObject*type,structPyModuleDef*def)¶
Find the first superclass whose module was created fromthe given
PyModuleDefdef, and return that module.If no module is found, raises a
TypeErrorand returnsNULL.This function is intended to be used together with
PyModule_GetState()to get module state from slot methods (such astp_initornb_add)and other places where a method’s defining class cannot be passed using thePyCMethodcalling convention.New in version 3.11.
Creating Heap-Allocated Types¶
The following functions and structs are used to createheap types.
- PyObject*PyType_FromModuleAndSpec(PyObject*module,PyType_Spec*spec,PyObject*bases)¶
- Return value: New reference. Part of theStable ABI since version 3.10.
Creates and returns aheap type from thespec(
Py_TPFLAGS_HEAPTYPE).Thebases argument can be used to specify base classes; it can eitherbe only one class or a tuple of classes.Ifbases is
NULL, thePy_tp_bases slot is used instead.If that also isNULL, thePy_tp_base slot is used instead.If that also isNULL, the new type derives fromobject.Themodule argument can be used to record the module in which the newclass is defined. It must be a module object or
NULL.If notNULL, the module is associated with the new type and can later beretrieved withPyType_GetModule().The associated module is not inherited by subclasses; it must be specifiedfor each class individually.This function calls
PyType_Ready()on the new type.New in version 3.9.
Changed in version 3.10:The function now accepts a single class as thebases argument and
NULLas thetp_docslot.
- PyObject*PyType_FromSpecWithBases(PyType_Spec*spec,PyObject*bases)¶
- Return value: New reference. Part of theStable ABI since version 3.3.
Equivalent to
PyType_FromModuleAndSpec(NULL,spec,bases).New in version 3.3.
- PyObject*PyType_FromSpec(PyType_Spec*spec)¶
- Return value: New reference. Part of theStable ABI.
Equivalent to
PyType_FromSpecWithBases(spec,NULL).
- typePyType_Spec¶
- Part of theStable ABI (including all members).
Structure defining a type’s behavior.
- constchar*PyType_Spec.name¶
Name of the type, used to set
PyTypeObject.tp_name.
- intPyType_Spec.basicsize¶
- intPyType_Spec.itemsize¶
Size of the instance in bytes, used to set
PyTypeObject.tp_basicsizeandPyTypeObject.tp_itemsize.
- intPyType_Spec.flags¶
Type flags, used to set
PyTypeObject.tp_flags.If the
Py_TPFLAGS_HEAPTYPEflag is not set,PyType_FromSpecWithBases()sets it automatically.
- PyType_Slot*PyType_Spec.slots¶
Array of
PyType_Slotstructures.Terminated by the special slot value{0,NULL}.
- constchar*PyType_Spec.name¶
- typePyType_Slot¶
- Part of theStable ABI (including all members).
Structure defining optional functionality of a type, containing a slot IDand a value pointer.
- intPyType_Slot.slot¶
A slot ID.
Slot IDs are named like the field names of the structures
PyTypeObject,PyNumberMethods,PySequenceMethods,PyMappingMethodsandPyAsyncMethodswith an addedPy_prefix.For example, use:Py_tp_deallocto setPyTypeObject.tp_deallocPy_nb_addto setPyNumberMethods.nb_addPy_sq_lengthto setPySequenceMethods.sq_length
The following fields cannot be set at all using
PyType_SpecandPyType_Slot:Setting
Py_tp_basesorPy_tp_basemay beproblematic on some platforms.To avoid issues, use thebases argument ofPyType_FromSpecWithBases()instead.Changed in version 3.9:Slots in
PyBufferProcsmay be set in the unlimited API.Changed in version 3.11:
bf_getbufferandbf_releasebufferare now availableunder thelimited API.
- void*PyType_Slot.pfunc¶
The desired value of the slot. In most cases, this is a pointerto a function.
Slots other than
Py_tp_docmay not beNULL.
- intPyType_Slot.slot¶