Type Objects

typePyTypeObject
Μέρος τουΠεριορισμένο API (ως μια αδιαφανής κατασκευή).

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

PyTypeObjectPyType_Type
Μέρος τουΣταθερό ABI.

This is the type object for type objects; it is the same object astype in 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()
Μέρος τουΣταθερό ABI.

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

unsignedlongPyType_GetFlags(PyTypeObject*type)
Μέρος τουΣταθερό ABI.

Return thetp_flags member oftype. This function is primarilymeant for use withPy_LIMITED_API; the individual flag bits areguaranteed to be stable across Python releases, but access totp_flags itself is not part of thelimited API.

Added in version 3.2.

Άλλαξε στην έκδοση 3.4:The return type is nowunsignedlong rather thanlong.

PyObject*PyType_GetDict(PyTypeObject*type)

Return the type object’s internal namespace, which is otherwise onlyexposed via a read-only proxy (cls.__dict__).This is areplacement for accessingtp_dict directly.The returned dictionary must be treated as read-only.

This function is meant for specific embedding and language-binding cases,where direct access to the dict is necessary and indirect access(e.g. via the proxy orPyObject_GetAttr()) isn’t adequate.

Extension modules should continue to usetp_dict,directly or indirectly, when setting up their own types.

Added in version 3.12.

voidPyType_Modified(PyTypeObject*type)
Μέρος τουΣταθερό 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_AddWatcher(PyType_WatchCallbackcallback)

Registercallback as a type watcher. Return a non-negative integer IDwhich must be passed to future calls toPyType_Watch(). In case oferror (e.g. no more watcher IDs available), return-1 and set anexception.

In free-threaded builds,PyType_AddWatcher() is not thread-safe,so it must be called at start up (before spawning the first thread).

Added in version 3.12.

intPyType_ClearWatcher(intwatcher_id)

Clear watcher identified bywatcher_id (previously returned fromPyType_AddWatcher()). Return0 on success,-1 on error (e.g.ifwatcher_id was never registered.)

An extension should never callPyType_ClearWatcher with awatcher_idthat was not returned to it by a previous call toPyType_AddWatcher().

Added in version 3.12.

intPyType_Watch(intwatcher_id,PyObject*type)

Marktype as watched. The callback grantedwatcher_id byPyType_AddWatcher() will be called wheneverPyType_Modified() reports a change totype. (The callback may becalled only once for a series of consecutive modifications totype, if_PyType_Lookup() is not called ontype between the modifications;this is an implementation detail and subject to change.)

An extension should never callPyType_Watch with awatcher_id that wasnot returned to it by a previous call toPyType_AddWatcher().

Added in version 3.12.

typedefint(*PyType_WatchCallback)(PyObject*type)

Type of a type-watcher callback function.

The callback must not modifytype or causePyType_Modified() to becalled ontype or any type in its MRO; violating this rule could causeinfinite recursion.

Added in version 3.12.

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 flagPy_TPFLAGS_HAVE_GC.

intPyType_IsSubtype(PyTypeObject*a,PyTypeObject*b)
Μέρος τουΣταθερό 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)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI.

Generic handler for thetp_alloc slot 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)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI.

Generic handler for thetp_new slot of a type object. Create anew instance using the type’stp_alloc slot.

intPyType_Ready(PyTypeObject*type)
Μέρος τουΣταθερό 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. Return0 on success, or return-1 and sets anexception on error.

Σημείωση

If some of the base classes implements the GC protocol and the providedtype does not include thePy_TPFLAGS_HAVE_GC in its flags, thenthe GC protocol will be automatically implemented from its parents. Onthe contrary, if the type being created does includePy_TPFLAGS_HAVE_GC in its flags then itmust implement theGC protocol itself by at least implementing thetp_traverse handle.

PyObject*PyType_GetName(PyTypeObject*type)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI από την έκδοση 3.11.

Return the type’s name. Equivalent to getting the type’s__name__ attribute.

Added in version 3.11.

PyObject*PyType_GetQualName(PyTypeObject*type)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI από την έκδοση 3.11.

Return the type’s qualified name. Equivalent to getting thetype’s__qualname__ attribute.

Added in version 3.11.

PyObject*PyType_GetFullyQualifiedName(PyTypeObject*type)
Μέρος τουΣταθερό ABI από την έκδοση 3.13.

Return the type’s fully qualified name. Equivalent tof"{type.__module__}.{type.__qualname__}", ortype.__qualname__iftype.__module__ is not a string or is equal to"builtins".

Added in version 3.13.

PyObject*PyType_GetModuleName(PyTypeObject*type)
Μέρος τουΣταθερό ABI από την έκδοση 3.13.

Return the type’s module name. Equivalent to getting thetype.__module__ attribute.

Added in version 3.13.

void*PyType_GetSlot(PyTypeObject*type,intslot)
Μέρος τουΣταθερό ABI από την έκδοση 3.4.

Return the function pointer stored in the given slot. If theresult isNULL, 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.

SeePyType_Slot.slot for possible values of theslot argument.

Added in version 3.4.

Άλλαξε στην έκδοση 3.10:PyType_GetSlot() can now accept all types.Previously, it was limited toheap types.

PyObject*PyType_GetModule(PyTypeObject*type)
Μέρος τουΣταθερό ABI από την έκδοση 3.10.

Return the module object associated with the given type when the type wascreated usingPyType_FromModuleAndSpec().

If no module is associated with the given type, setsTypeErrorand 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.SeePyCMethod to get the class that defines the method.SeePyType_GetModuleByDef() for cases whenPyCMethod cannotbe used.

Added in version 3.9.

void*PyType_GetModuleState(PyTypeObject*type)
Μέρος τουΣταθερό ABI από την έκδοση 3.10.

Return the state of the module object associated with the given type.This is a shortcut for callingPyModule_GetState() on the resultofPyType_GetModule().

If no module is associated with the given type, setsTypeErrorand returnsNULL.

If thetype has an associated module but its state isNULL,returnsNULL without setting an exception.

Added in version 3.9.

PyObject*PyType_GetModuleByDef(PyTypeObject*type,structPyModuleDef*def)
Μέρος τουΣταθερό ABI από την έκδοση 3.13.

Find the first superclass whose module was created fromthe givenPyModuleDefdef, and return that module.

If no module is found, raises aTypeError and returnsNULL.

This function is intended to be used together withPyModule_GetState() to get module state from slot methods (such astp_init ornb_add)and other places where a method’s defining class cannot be passed using thePyCMethod calling convention.

Added in version 3.11.

intPyType_GetBaseByToken(PyTypeObject*type,void*token,PyTypeObject**result)
Μέρος τουΣταθερό ABI από την έκδοση 3.14.

Find the first superclass intype’smethod resolution order whosePy_tp_token token is equal to the given one.

  • If found, set*result to a newstrong referenceto it and return1.

  • If not found, set*result toNULL and return0.

  • On error, set*result toNULL and return-1 with anexception set.

Theresult argument may beNULL, in which case*result is not set.Use this if you need only the return value.

Thetoken argument may not beNULL.

Added in version 3.14.

intPyUnstable_Type_AssignVersionTag(PyTypeObject*type)
Αυτό είναιΑσταθές API. Μπορεί να αλλάξει χωρίς προειδοποίηση σε μικρές εκδόσεις.

Attempt to assign a version tag to the given type.

Returns 1 if the type already had a valid version tag or a new one wasassigned, or 0 if a new tag could not be assigned.

Added in version 3.12.

Creating Heap-Allocated Types

The following functions and structs are used to createheap types.

PyObject*PyType_FromMetaclass(PyTypeObject*metaclass,PyObject*module,PyType_Spec*spec,PyObject*bases)
Μέρος τουΣταθερό ABI από την έκδοση 3.12.

Create and return aheap type from thespec(seePy_TPFLAGS_HEAPTYPE).

The metaclassmetaclass is used to construct the resulting type object.Whenmetaclass isNULL, the metaclass is derived frombases(orPy_tp_base[s] slots ifbases isNULL, see below).

Metaclasses that overridetp_new are notsupported, except iftp_new isNULL.

Thebases argument can be used to specify base classes; it can eitherbe only one class or a tuple of classes.Ifbases isNULL, 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 orNULL.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 callsPyType_Ready() on the new type.

Note that this function doesnot fully match the behavior ofcallingtype() or using theclass statement.With user-provided base types or metaclasses, prefercallingtype (or the metaclass)overPyType_From* functions.Specifically:

Added in version 3.12.

PyObject*PyType_FromModuleAndSpec(PyObject*module,PyType_Spec*spec,PyObject*bases)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI από την έκδοση 3.10.

Equivalent toPyType_FromMetaclass(NULL,module,spec,bases).

Added in version 3.9.

Άλλαξε στην έκδοση 3.10:The function now accepts a single class as thebases argument andNULL as thetp_doc slot.

Άλλαξε στην έκδοση 3.12:The function now finds and uses a metaclass corresponding to the providedbase classes. Previously, onlytype instances were returned.

Thetp_new of the metaclass isignored.which may result in incomplete initialization.Creating classes whose metaclass overridestp_new is deprecated.

Άλλαξε στην έκδοση 3.14:Creating classes whose metaclass overridestp_new is no longer allowed.

PyObject*PyType_FromSpecWithBases(PyType_Spec*spec,PyObject*bases)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI από την έκδοση 3.3.

Equivalent toPyType_FromMetaclass(NULL,NULL,spec,bases).

Added in version 3.3.

Άλλαξε στην έκδοση 3.12:The function now finds and uses a metaclass corresponding to the providedbase classes. Previously, onlytype instances were returned.

Thetp_new of the metaclass isignored.which may result in incomplete initialization.Creating classes whose metaclass overridestp_new is deprecated.

Άλλαξε στην έκδοση 3.14:Creating classes whose metaclass overridestp_new is no longer allowed.

PyObject*PyType_FromSpec(PyType_Spec*spec)
Επιστρεφόμενη τιμή: New reference. Μέρος τουΣταθερό ABI.

Equivalent toPyType_FromMetaclass(NULL,NULL,spec,NULL).

Άλλαξε στην έκδοση 3.12:The function now finds and uses a metaclass corresponding to thebase classes provided inPy_tp_base[s] slots.Previously, onlytype instances were returned.

Thetp_new of the metaclass isignored.which may result in incomplete initialization.Creating classes whose metaclass overridestp_new is deprecated.

Άλλαξε στην έκδοση 3.14:Creating classes whose metaclass overridestp_new is no longer allowed.

intPyType_Freeze(PyTypeObject*type)
Μέρος τουΣταθερό ABI από την έκδοση 3.14.

Make a type immutable: set thePy_TPFLAGS_IMMUTABLETYPE flag.

All base classes oftype must be immutable.

On success, return0.On error, set an exception and return-1.

The type must not be used before it’s made immutable. For example, typeinstances must not be created before the type is made immutable.

Added in version 3.14.

typePyType_Spec
Μέρος τουΣταθερό ABI (συμπεριλαμβανομένων όλων των μελών).

Structure defining a type’s behavior.

constchar*name

Name of the type, used to setPyTypeObject.tp_name.

intbasicsize

If positive, specifies the size of the instance in bytes.It is used to setPyTypeObject.tp_basicsize.

If zero, specifies thattp_basicsizeshould be inherited.

If negative, the absolute value specifies how much space instances of theclass needin addition to the superclass.UsePyObject_GetTypeData() to get a pointer to subclass-specificmemory reserved this way.For negativebasicsize, Python will insert padding whenneeded to meettp_basicsize’s alignmentrequirements.

Άλλαξε στην έκδοση 3.12:Previously, this field could not be negative.

intitemsize

Size of one element of a variable-size type, in bytes.Used to setPyTypeObject.tp_itemsize.Seetp_itemsize documentation for caveats.

If zero,tp_itemsize is inherited.Extending arbitrary variable-sized classes is dangerous,since some types use a fixed offset for variable-sized memory,which can then overlap fixed-sized memory used by a subclass.To help prevent mistakes, inheritingitemsize is only possiblein the following situations:

unsignedintflags

Type flags, used to setPyTypeObject.tp_flags.

If thePy_TPFLAGS_HEAPTYPE flag is not set,PyType_FromSpecWithBases() sets it automatically.

PyType_Slot*slots

Array ofPyType_Slot structures.Terminated by the special slot value{0,NULL}.

Each slot ID should be specified at most once.

typePyType_Slot
Μέρος τουΣταθερό ABI (συμπεριλαμβανομένων όλων των μελών).

Structure defining optional functionality of a type, containing a slot IDand a value pointer.

intslot

A slot ID.

Slot IDs are named like the field names of the structuresPyTypeObject,PyNumberMethods,PySequenceMethods,PyMappingMethods andPyAsyncMethods with an addedPy_ prefix.For example, use:

An additional slot is supported that does not correspond to aPyTypeObject struct field:

The following “offset” fields cannot be set usingPyType_Slot:

If it is not possible to switch to aMANAGED flag (for example,for vectorcall or to support Python older than 3.12), specify theoffset inPy_tp_members.SeePyMemberDef documentationfor details.

The following internal fields cannot be set at all when creating a heaptype:

SettingPy_tp_bases orPy_tp_base may beproblematic on some platforms.To avoid issues, use thebases argument ofPyType_FromSpecWithBases() instead.

Άλλαξε στην έκδοση 3.9:Slots inPyBufferProcs may be set in the unlimited API.

Άλλαξε στην έκδοση 3.11:bf_getbuffer andbf_releasebuffer are now availableunder thelimited API.

Άλλαξε στην έκδοση 3.14:The fieldtp_vectorcall can now setusingPy_tp_vectorcall. See the field’s documentationfor details.

void*pfunc

The desired value of the slot. In most cases, this is a pointerto a function.

pfunc values may not beNULL, except for the following slots:

Py_tp_token

Aslot that records a static memory layout IDfor a class.

If thePyType_Spec of the class is staticallyallocated, the token can be set to the spec using the special valuePy_TP_USE_SPEC:

staticPyType_Slotfoo_slots[]={{Py_tp_token,Py_TP_USE_SPEC},

It can also be set to an arbitrary pointer, but you must ensure that:

  • The pointer outlives the class, so it’s not reused for something elsewhile the class exists.

  • It «belongs» to the extension module where the class lives, so it will notclash with other extensions.

UsePyType_GetBaseByToken() to check if a class’s superclass hasa given token – that is, check whether the memory layout is compatible.

To get the token for a given class (without considering superclasses),usePyType_GetSlot() withPy_tp_token.

Added in version 3.14.

Py_TP_USE_SPEC

Used as a value withPy_tp_token to set the token to theclass’sPyType_Spec.Expands toNULL.

Added in version 3.14.