型別物件

type PyTypeObject

為 穩定 ABI 的一部分 （做為一個不透明結構 (opaque struct)）.

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

PyTypeObject PyType_Type

為 穩定 ABI 的一部分.

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 non-zero if the object o is a type object, including instances of types derived from the standard type object. Return 0 in all other cases. This function always succeeds.

int PyType_CheckExact(PyObject *o)

Return non-zero if the object o is a type object, but not a subtype of the standard type object. Return 0 in all other cases. This function always succeeds.

unsigned int PyType_ClearCache()

為 穩定 ABI 的一部分.

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

unsigned long PyType_GetFlags(PyTypeObject *type)

為 穩定 ABI 的一部分.

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.

在 3.2 版被加入.

在 3.4 版的變更: The return type is now unsigned long rather than long.

PyObject *PyType_GetDict(PyTypeObject *type)

Return the type object's internal namespace, which is otherwise only exposed via a read-only proxy (cls.__dict__). This is a replacement for accessing tp_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 or PyObject_GetAttr()) isn't adequate.

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

在 3.12 版被加入.

void PyType_Modified(PyTypeObject *type)

為 穩定 ABI 的一部分.

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_AddWatcher(PyType_WatchCallback callback)

Register callback as a type watcher. Return a non-negative integer ID which must be passed to future calls to PyType_Watch(). In case of error (e.g. no more watcher IDs available), return -1 and set an exception.

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

在 3.12 版被加入.

int PyType_ClearWatcher(int watcher_id)

Clear watcher identified by watcher_id (previously returned from PyType_AddWatcher()). Return 0 on success, -1 on error (e.g. if watcher_id was never registered.)

An extension should never call PyType_ClearWatcher with a watcher_id that was not returned to it by a previous call to PyType_AddWatcher().

在 3.12 版被加入.

int PyType_Watch(int watcher_id, PyObject *type)

Mark type as watched. The callback granted watcher_id by PyType_AddWatcher() will be called whenever PyType_Modified() reports a change to type. (The callback may be called only once for a series of consecutive modifications to type, if _PyType_Lookup() is not called on type between the modifications; this is an implementation detail and subject to change.)

The callback is also invoked when a watched heap type is deallocated.

An extension should never call PyType_Watch with a watcher_id that was not returned to it by a previous call to PyType_AddWatcher().

在 3.12 版被加入.

在 3.15 版的變更: The callback is now also invoked when a watched heap type is deallocated.

int PyType_Unwatch(int watcher_id, PyObject *type)

Mark type as not watched. This undoes a previous call to PyType_Watch(). type must not be NULL.

An extension should never call this function with a watcher_id that was not returned to it by a previous call to PyType_AddWatcher().

成功時此函式會回傳 0。失敗時此函式回傳 -1 並設定例外。

在 3.12 版被加入.

typedef int (*PyType_WatchCallback)(PyObject *type)

Type of a type-watcher callback function.

The callback must not modify type or cause PyType_Modified() to be called on type or any type in its MRO; violating this rule could cause infinite recursion.

The callback may be called during type deallocation. In this case, the type object is temporarily resurrected (its reference count is at least 1) and all its attributes are still valid. However, the callback should not store new strong references to the type, as this would resurrect the object and prevent its deallocation.

在 3.12 版被加入.

在 3.15 版的變更: The callback may now be called during deallocation of a watched heap type.

int PyType_HasFeature(PyTypeObject *o, int feature)

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

int PyType_FastSubclass(PyTypeObject *type, int flag)

Return non-zero if the type object type sets the subclass flag flag. Subclass flags are denoted by Py_TPFLAGS_*_SUBCLASS. This function is used by many _Check functions for common types.

也參考

PyObject_TypeCheck(), which is used as a slower alternative in _Check functions for types that don't come with subclass 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)

為 穩定 ABI 的一部分.

如果 a 是 b 的子類別則回傳 true。

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)

回傳值：新的參照。 為 穩定 ABI 的一部分.

Generic handler for the tp_alloc slot of a type object. Uses Python's default memory allocation mechanism to allocate memory for a new instance, zeros the memory, then initializes the memory as if by calling PyObject_Init() or PyObject_InitVar().

Do not call this directly to allocate memory for an object; call the type's tp_alloc slot instead.

For types that support garbage collection (i.e., the Py_TPFLAGS_HAVE_GC flag is set), this function behaves like PyObject_GC_New or PyObject_GC_NewVar (except the memory is guaranteed to be zeroed before initialization), and should be paired with PyObject_GC_Del() in tp_free. Otherwise, it behaves like PyObject_New or PyObject_NewVar (except the memory is guaranteed to be zeroed before initialization) and should be paired with PyObject_Free() in tp_free.

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

回傳值：新的參照。 為 穩定 ABI 的一部分.

Generic handler for the tp_new slot of a type object. Creates a new instance using the type's tp_alloc slot and returns the resulting object.

int PyType_Ready(PyTypeObject *type)

為 穩定 ABI 的一部分.

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.

備註

If some of the base classes implements the GC protocol and the provided type does not include the Py_TPFLAGS_HAVE_GC in its flags, then the GC protocol will be automatically implemented from its parents. On the contrary, if the type being created does include Py_TPFLAGS_HAVE_GC in its flags then it must implement the GC protocol itself by at least implementing the tp_traverse handle.

PyObject *PyType_GetName(PyTypeObject *type)

回傳值：新的參照。 為 穩定 ABI 的一部分 自 3.11 版本開始.

Return the type's name. Equivalent to getting the type's __name__ attribute.

在 3.11 版被加入.

PyObject *PyType_GetQualName(PyTypeObject *type)

回傳值：新的參照。 為 穩定 ABI 的一部分 自 3.11 版本開始.

Return the type's qualified name. Equivalent to getting the type's __qualname__ attribute.

在 3.11 版被加入.

PyObject *PyType_GetFullyQualifiedName(PyTypeObject *type)

為 穩定 ABI 的一部分 自 3.13 版本開始.

Return the type's fully qualified name. Equivalent to f"{type.__module__}.{type.__qualname__}", or type.__qualname__ if type.__module__ is not a string or is equal to "builtins".

在 3.13 版被加入.

PyObject *PyType_GetModuleName(PyTypeObject *type)

為 穩定 ABI 的一部分 自 3.13 版本開始.

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

在 3.13 版被加入.

void *PyType_GetSlot(PyTypeObject *type, int slot)

為 穩定 ABI 的一部分 自 3.4 版本開始.

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.

See PyType_Slot.slot for possible values of the slot argument.

在 3.4 版被加入.

在 3.10 版的變更: PyType_GetSlot() can now accept all types. Previously, it was limited to heap types.

PyObject *PyType_GetModule(PyTypeObject *type)

回傳值：借用參照。 為 穩定 ABI 的一部分 自 3.10 版本開始.

Return the module object associated with the given type when the type was created using PyType_FromModuleAndSpec().

The returned reference is borrowed from type, and will be valid as long as you hold a reference to type. Do not release it with Py_DECREF() or similar.

If no module is associated with the given type, sets TypeError and returns NULL.

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 a subclass of the intended class, and subclasses are not necessarily defined in the same module as their superclass. See PyCMethod to get the class that defines the method. See PyType_GetModuleByToken() for cases when PyCMethod cannot be used.

在 3.9 版被加入.

void *PyType_GetModuleState(PyTypeObject *type)

為 穩定 ABI 的一部分 自 3.10 版本開始.

Return the state of the module object associated with the given type. This is a shortcut for calling PyModule_GetState() on the result of PyType_GetModule().

If no module is associated with the given type, sets TypeError and returns NULL.

If the type has an associated module but its state is NULL, returns NULL without setting an exception.

在 3.9 版被加入.

PyObject *PyType_GetModuleByToken(PyTypeObject *type, const void *mod_token)

回傳值：新的參照。 為 穩定 ABI 的一部分 自 3.15 版本開始.

Find the first superclass whose module has the given module token, and return that module.

If no module is found, raises a TypeError and returns NULL.

This function is intended to be used together with PyModule_GetState() to get module state from slot methods (such as tp_init or nb_add) and other places where a method's defining class cannot be passed using the PyCMethod calling convention.

在 3.15 版被加入.

PyObject *PyType_GetModuleByDef(PyTypeObject *type, struct PyModuleDef *def)

回傳值：借用參照。 為 穩定 ABI 的一部分 自 3.13 版本開始.

Find the first superclass whose module was created from the given PyModuleDef def, or whose module token is equal to def, and return that module.

Note that modules created from a PyModuleDef always have their token set to the PyModuleDef's address. In other words, this function is equivalent to PyType_GetModuleByToken(), except that it:

• returns a borrowed reference, and

• has a non-void* argument type (which is a cosmetic difference in C).

The returned reference is borrowed from type, and will be valid as long as you hold a reference to type. Do not release it with Py_DECREF() or similar.

在 3.11 版被加入.

int PyType_GetBaseByToken(PyTypeObject *type, void *tp_token, PyTypeObject **result)

為 穩定 ABI 的一部分 自 3.14 版本開始.

Find the first superclass in type's method resolution order whose Py_tp_token token is equal to tp_token.

• If found, set *result to a new strong reference to it and return 1.

• 如果沒找到，則將 *result 設為 NULL 並回傳 0。

• 在發生錯誤時，將 *result 設為 NULL 並回傳 -1，同時設定例外。

如果 result 引數為 NULL，則不會設定 *result。如果你只需要回傳值，請使用此選項。

The tp_token argument may not be NULL.

在 3.14 版被加入.

int PyUnstable_Type_AssignVersionTag(PyTypeObject *type)

這是 不穩定 API，它可能在小版本發布中沒有任何警告地被變更。

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 was assigned, or 0 if a new tag could not be assigned.

在 3.12 版被加入.

int PyType_SUPPORTS_WEAKREFS(PyTypeObject *type)

Return true if instances of type support creating weak references, false otherwise. This function always succeeds. type must not be NULL.

也參考

• 弱參照物件

• weakref

Creating Heap-Allocated Types

The following function is used to create heap types:

PyObject *PyType_FromSlots(const PySlot *slots)

為 穩定 ABI 的一部分 自 3.15 版本開始.

Create and return a heap type from a PySlot array. See Definition slots for general information on slots, and Type slot IDs for slots specific to type creation.

This function calls PyType_Ready() on the new type.

Note that this function does not fully match the behavior of calling type() or using the class statement. With user-provided base types or metaclasses, prefer calling type (or the metaclass) over PyType_From* functions. Specifically:

• __new__() 不會在新類別上被呼叫（且它必須被設為 type.__new__）。

• __init__() 不會在新類別上被呼叫。

• __init_subclass__() 不會在任何基底上被呼叫。

• __set_name__() 不會在新的描述器上被呼叫。

Slots are typically defined as a global static constant arrays. However, sometimes slot values are not statically known at compile time. For example, slots like Py_tp_bases, Py_tp_metaclass and Py_tp_module require live Python objects. In this case, it is recommended to put such slots on the stack, and use Py_slot_subslots to refer to an array of static slots. For example:

static const PySlot my_slots[] = {
   PySlot_STATIC_DATA(Py_tp_name, "MyClass"),
   PySlot_FUNC(Py_tp_repr, my_repr_func),
   ...
   PySlot_END
};

PyObject *make_my_class(PyObject *module) {
   PySlot all_slots[] = {
      PySlot_STATIC_DATA(Py_slot_subslots, my_slots),
      PySlot_DATA(Py_tp_module, module),
      PySlot_END
   };
   return PyType_FromSlots(all_slots);
}

Heap types created without the Py_TPFLAGS_IMMUTABLETYPE flag may be modified, for example by setting attributes on them, as with classes defined in Python code. Sometimes, such modifications are necessary to fully initialize a type, but you may wish to prevent users from changing the type after the initialization is done:

int PyType_Freeze(PyTypeObject *type)

為 穩定 ABI 的一部分 自 3.14 版本開始.

Make a type immutable: set the Py_TPFLAGS_IMMUTABLETYPE flag.

所有 type 的基底類別都必須是不可變的。

On success, return 0. On error, set an exception and return -1.

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

在 3.14 版被加入.

Type slot IDs

Most type slot IDs are named like the field names of the structures PyTypeObject, PyNumberMethods, PySequenceMethods, PyMappingMethods and PyAsyncMethods with an added Py_ prefix. For example, use:

• Py_tp_dealloc 以設定 PyTypeObject.tp_dealloc

• Py_nb_add 以設定 PyNumberMethods.nb_add

• Py_sq_length 以設定 PySequenceMethods.sq_length

The following slots need additional considerations when specified as slots:

• Py_tp_name

• Py_tp_basicsize and Py_tp_extra_basicsize

• Py_tp_itemsize

• Py_tp_flags

Additional slots do not directly correspond to a PyTypeObject struct field:

• Py_tp_token

• Py_tp_metaclass

• Py_tp_module

The following “offset” fields cannot be set using PyType_Slot:

• tp_weaklistoffset（如果可能，請改用 Py_TPFLAGS_MANAGED_WEAKREF）

• tp_dictoffset（如果可能，請改用 Py_TPFLAGS_MANAGED_DICT）

• tp_vectorcall_offset（請用 PyMemberDef 中的 "__vectorcalloffset__"）

If it is not possible to switch to a MANAGED flag (for example, for vectorcall or to support Python older than 3.12), specify the offset in Py_tp_members. See PyMemberDef documentation for details.

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

• tp_dict, tp_mro, tp_cache, tp_subclasses, and tp_weaklist.

The Py_tp_base slot is equivalent to Py_tp_bases; both may be set either to a type or a tuple of types. If both are specified, the value of Py_tp_bases is used.

Slot values may not be NULL, except for the following:

• Py_tp_doc

• Py_tp_token (for clarity, prefer Py_TP_USE_SPEC rather than NULL)

在 3.9 版的變更: Slots in PyBufferProcs may be set in the unlimited API.

在 3.11 版的變更: bf_getbuffer and bf_releasebuffer are now available under the limited API.

在 3.14 版的變更: The field tp_vectorcall can now be set using Py_tp_vectorcall. See the field's documentation for details.

在 3.15 版的變更: The Py_tp_bases slot may be set to a single type object, making it equivalent to the Py_tp_base slot. Previously, a tuple of types was required.

The following slots correspond to fields in the underlying type structure, but need extra remarks for use as slots:

Py_tp_name

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for the name of the type, used to set PyTypeObject.tp_name.

This slot (or PyType_Spec.name()) is required to create a type.

This may not be used in PyType_Spec.slots. Use PyType_Spec.name() instead.

CPython 實作細節： CPython processes slots in order. It is recommended to put Py_tp_name at the beginning of the slots array, so that if processing of a later slots fails, error messages can include the name.

在 3.15 版被加入.

Py_tp_basicsize

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for the size of the instance in bytes. It is used to set PyTypeObject.tp_basicsize.

The value must be positive.

This may not be used in PyType_Spec.slots. Use PyType_Spec.basicsize() instead.

This slot may not be used with PyType_GetSlot(). Use PyTypeObject.tp_basicsize instead if needed, but be aware that a type's size is often considered an implementation detail.

在 3.15 版被加入.

Py_tp_extra_basicsize

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for type data size in bytes, that is, how much space instances of the class need in addition to space needed for superclasses.

The value is used, together with the size of superclasses, to set PyTypeObject.tp_basicsize. Python will insert padding as needed to meet tp_basicsize's alignment requirements.

Use PyObject_GetTypeData() to get a pointer to subclass-specific memory reserved this way.

The value must be positive. To specify that instances need no additional size (that is, size should be inherited), omit the Py_tp_extra_basicsize slot rather than set it to zero.

Specifying both Py_tp_basicsize and Py_tp_extra_basicsize is an error.

This may not be used in PyType_Spec.slots. Use negative PyType_Spec.basicsize() instead.

This slot may not be used with PyType_GetSlot().

在 3.15 版被加入.

Py_tp_itemsize

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for the size of one element of a variable-size type, in bytes. Used to set PyTypeObject.tp_itemsize. See tp_itemsize documentation for caveats.

The value must be positive.

If this slot is missing, 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, inheriting itemsize is only possible in the following situations:

• The base is not variable-sized (its tp_itemsize).

• The requested PyType_Spec.basicsize is positive, suggesting that the memory layout of the base class is known.

• The requested PyType_Spec.basicsize is zero, suggesting that the subclass does not access the instance's memory directly.

• With the Py_TPFLAGS_ITEMS_AT_END flag.

This may not be used in PyType_Spec.slots. Use PyType_Spec.itemsize() instead.

This slot may not be used with PyType_GetSlot().

在 3.15 版被加入.

Py_tp_flags

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for type flags, used to set PyTypeObject.tp_flags.

The Py_TPFLAGS_HEAPTYPE flag is not set, PyType_FromSpecWithBases() sets it automatically.

This may not be used in PyType_Spec.slots. Use negative PyType_Spec.basicsize() instead.

This slot may not be used with PyType_GetSlot(). Use PyType_GetFlags() instead.

在 3.15 版被加入.

The following slots do not correspond to public fields in the underlying structures:

Py_tp_metaclass

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for the metaclass used to construct the resulting type object. When omitted the metaclass is derived from bases (Py_tp_bases or the bases argument of PyType_FromMetaclass()).

Metaclasses that override tp_new are not supported, except if tp_new is NULL.

This may not be used in PyType_Spec.slots. Use PyType_FromMetaclass() to specify a metaclass with PyType_Spec.

This slot may not be used with PyType_GetSlot(). Use Py_TYPE() on the type object instead.

在 3.15 版被加入.

Py_tp_module

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID for recording the module in which the new class is defined.

The value must be a module object. The module is associated with the new type and can later be retrieved with PyType_GetModule(). The associated module is not inherited by subclasses; it must be specified for each class individually.

This may not be used in PyType_Spec.slots. Use PyType_FromMetaclass() to specify a module with PyType_Spec.

This slot may not be used with PyType_GetSlot(). Use PyType_GetModule() instead.

在 3.15 版被加入.

Py_tp_token

為 穩定 ABI 的一部分 自 3.14 版本開始.

Slot ID for recording a static memory layout ID for a class.

If the class is defined using a PyType_Spec, and that spec is statically allocated, the token can be set to the spec using the special value Py_TP_USE_SPEC:

static PyType_Slot foo_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 else while the class exists.

• It "belongs" to the extension module where the class lives, so it will not clash with other extensions.

Use PyType_GetBaseByToken() to check if a class's superclass has a given token -- that is, check whether the memory layout is compatible.

To get the token for a given class (without considering superclasses), use PyType_GetSlot() with Py_tp_token.

在 3.14 版被加入.

Py_TP_USE_SPEC

為 穩定 ABI 的一部分 自 3.14 版本開始.

Used as a value with Py_tp_token to set the token to the class's PyType_Spec. May only be used for classes defined using PyType_Spec.

Expands to NULL.

在 3.14 版被加入.

Py_tp_slots

為 穩定 ABI 的一部分 自 3.15 版本開始.

Slot ID that works like Py_slot_subslots, except it specifies an array of PyType_Slot structures.

在 3.15 版被加入.

Soft-deprecated API

The following functions are soft deprecated. They will continue to work, but new features will be added as slots for PyType_FromSlots(), not as arguments to new PyType_From* functions.

PyObject *PyType_FromMetaclass(PyTypeObject *metaclass, PyObject *module, PyType_Spec *spec, PyObject *bases)

為 穩定 ABI 的一部分 自 3.12 版本開始.

Create and return a heap type from the spec (see Py_TPFLAGS_HEAPTYPE).

A non-NULL metaclass argument corresponds to the Py_tp_metaclass slot.

A non-NULL bases argument corresponds to the Py_tp_bases slot, and takes precedence over Py_tp_bases and Py_tp_bases slots.

A non-NULL module argument corresponds to the Py_tp_module slot.

This function calls PyType_Ready() on the new type.

Note that this function does not fully match the behavior of calling type() or using the class statement. See the note in PyType_FromSlots() documentation for details.

在 3.12 版被加入.

Soft deprecated since version 3.15.0b1 (unreleased): Prefer PyType_FromSlots() in new code.

PyObject *PyType_FromModuleAndSpec(PyObject *module, PyType_Spec *spec, PyObject *bases)

回傳值：新的參照。 為 穩定 ABI 的一部分 自 3.10 版本開始.

等價於 PyType_FromMetaclass(NULL, module, spec, bases)。

在 3.9 版被加入.

在 3.10 版的變更: The function now accepts a single class as the bases argument and NULL as the tp_doc slot.

在 3.12 版的變更: The function now finds and uses a metaclass corresponding to the provided base classes. Previously, only type instances were returned.

The tp_new of the metaclass is ignored. which may result in incomplete initialization. Creating classes whose metaclass overrides tp_new is deprecated.

在 3.14 版的變更: Creating classes whose metaclass overrides tp_new is no longer allowed.

Soft deprecated since version 3.15.0b1 (unreleased): Prefer PyType_FromSlots() in new code.

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

回傳值：新的參照。 為 穩定 ABI 的一部分 自 3.3 版本開始.

等價於 PyType_FromMetaclass(NULL, NULL, spec, bases)。

在 3.3 版被加入.

在 3.12 版的變更: The function now finds and uses a metaclass corresponding to the provided base classes. Previously, only type instances were returned.

The tp_new of the metaclass is ignored. which may result in incomplete initialization. Creating classes whose metaclass overrides tp_new is deprecated.

在 3.14 版的變更: Creating classes whose metaclass overrides tp_new is no longer allowed.

Soft deprecated since version 3.15.0b1 (unreleased): Prefer PyType_FromSlots() in new code.

PyObject *PyType_FromSpec(PyType_Spec *spec)

回傳值：新的參照。 為 穩定 ABI 的一部分.

等價於 PyType_FromMetaclass(NULL, NULL, spec, NULL)。

在 3.12 版的變更: The function now finds and uses a metaclass corresponding to the base classes provided in Py_tp_base[s] slots. Previously, only type instances were returned.

The tp_new of the metaclass is ignored. which may result in incomplete initialization. Creating classes whose metaclass overrides tp_new is deprecated.

在 3.14 版的變更: Creating classes whose metaclass overrides tp_new is no longer allowed.

Soft deprecated since version 3.15.0b1 (unreleased): Prefer PyType_FromSlots() in new code.

type PyType_Spec

為 穩定 ABI 的一部分 （包含所有成員）.

Structure defining a type's behavior, used for soft-deprecated functions like PyType_FromMetaclass().

This structure contains several members that can instead be specified as slots for PyType_FromSlots(), and an array of slot entries with a simpler structure.

const char *name

Corresponds to Py_tp_name.

int basicsize

If positive, corresponds to Py_tp_basicsize.

If negative, corresponds to Py_tp_extra_basicsize set to the absolute value.

在 3.12 版的變更: 在過去此欄位不可為負值。

int itemsize

Corresponds to Py_tp_itemsize.

unsigned int flags

Corresponds to Py_tp_flags.

PyType_Slot *slots

Array of PyType_Slot (not PySlot) structures.

Terminated by the special slot value {0, NULL}. Each slot ID should be specified at most once.

type PyType_Slot

為 穩定 ABI 的一部分 （包含所有成員）.

Structure defining optional functionality of a type, used for soft-deprecated functions like PyType_FromMetaclass().

Note that a PyType_Slot array may be included in a PySlot array using Py_tp_slots, and vice versa using Py_slot_subslots.

Each PyType_Slot structure tpslot is interpreted as the following PySlot structure:

(PySlot){
   .sl_id=tpslot.slot,
   .sl_flags=PySlot_INTPTR | sub_static,
   .sl_ptr=tpslot.func
}

where sub_static is PySlot_STATIC if the slot requires the flag (such as for Py_tp_methods), or if this flag is present on the "parent" Py_tp_slots slot (if any).

int slot

Corresponds to PySlot.sl_id.

void *pfunc

Corresponds to PySlot.sl_ptr.