# Objetos tipo

type PyTypeObject
  Parte da API Limitada (como uma estrutura opaca).

  A estrutura C dos objetos usados para descrever tipos embutidos.

PyTypeObject PyType_Type
  Parte da ABI Estável.

  Este é o objeto de tipo para objetos tipo; é o mesmo objeto que `type` na camada Python.

int PyType_Check(PyObject *o)

  Retorna valor diferente de zero se o objeto o for um objeto tipo, incluindo instâncias de tipos derivados do objeto tipo padrão. Retorna 0 em todos os outros casos. Esta função sempre tem sucesso.

int PyType_CheckExact(PyObject *o)

  Retorna valor diferente de zero se o objeto o for um objeto tipo, mas não um subtipo do objeto tipo padrão. Retorna 0 em todos os outros casos. Esta função sempre tem sucesso.

unsigned int PyType_ClearCache()
  Parte da ABI Estável.

  Limpa o cache de pesquisa interno. Retorna a marcação de versão atual.

unsigned long PyType_GetFlags(PyTypeObject *type)
  Parte da ABI Estável.

  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.

  Adicionado na versão 3.2.

  Alterado na versão 3.4: O tipo de retorno é agora um `unsigned long` em vez de um `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.

  Adicionado na versão 3.12.

void PyType_Modified(PyTypeObject *type)
  Parte da ABI Estável.

  Invalida o cache de pesquisa interna para o tipo e todos os seus subtipos. Esta função deve ser chamada após qualquer modificação manual dos atributos ou classes bases do tipo.

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).

  Adicionado na versão 3.12.

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()`.

  Adicionado na versão 3.12.

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.)

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

  Adicionado na versão 3.12.

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.

  Adicionado na versão 3.12.

int PyType_HasFeature(PyTypeObject *o, int feature)

  Retorna valor diferente de zero se o objeto tipo o define o recurso feature. Os recursos de tipo são denotados por sinalizadores de bit único.

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)
  Parte da ABI Estável.

  Retorna verdadeiro se a for um subtipo de 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)
  Retorna valor: Nova referência. Parte da ABI Estável.

  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)
  Retorna valor: Nova referência. Parte da ABI Estável.

  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)
  Parte da ABI Estável.

  Finaliza um objeto tipo. Isso deve ser chamado em todos os objetos tipo para finalizar sua inicialização. Esta função é responsável por adicionar slots herdados da classe base de um tipo. Retorna `0` em caso de sucesso, ou retorna `-1` e define uma exceção em caso de erro.

  Nota

  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)
  Retorna valor: Nova referência. Parte da ABI Estável desde a versão 3.11.

  Return the type’s name. Equivalent to getting the type’s `__name__` attribute.

  Adicionado na versão 3.11.

PyObject *PyType_GetQualName(PyTypeObject *type)
  Retorna valor: Nova referência. Parte da ABI Estável desde a versão 3.11.

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

  Adicionado na versão 3.11.

PyObject *PyType_GetFullyQualifiedName(PyTypeObject *type)
  Parte da ABI Estável desde a versão 3.13.

  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"`.

  Adicionado na versão 3.13.

PyObject *PyType_GetModuleName(PyTypeObject *type)
  Parte da ABI Estável desde a versão 3.13.

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

  Adicionado na versão 3.13.

void *PyType_GetSlot(PyTypeObject *type, int slot)
  Parte da ABI Estável desde a versão 3.4.

  Retorna o ponteiro de função armazenado no slot fornecido. Se o resultado for `NULL`, isso indica que o slot é `NULL` ou que a função foi chamada com parâmetros inválidos. Os chamadores normalmente lançarão o ponteiro do resultado no tipo de função apropriado.

  Veja `PyType_Slot.slot` por possíveis valores do argumento slot.

  Adicionado na versão 3.4.

  Alterado na versão 3.10: `PyType_GetSlot()` can now accept all types. Previously, it was limited to heap types.

PyObject *PyType_GetModule(PyTypeObject *type)
  Parte da ABI Estável desde a versão 3.10.

  Retorna o objeto de módulo associado ao tipo fornecido quando o tipo foi criado usando `PyType_FromModuleAndSpec()`.

  Se nenhum módulo estiver associado com o tipo fornecido, define `TypeError` e retorna `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_GetModuleByDef()` for cases when `PyCMethod` cannot be used.

  Adicionado na versão 3.9.

void *PyType_GetModuleState(PyTypeObject *type)
  Parte da ABI Estável desde a versão 3.10.

  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()`.

  Se nenhum módulo estiver associado com o tipo fornecido, define `TypeError` e retorna `NULL`.

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

  Adicionado na versão 3.9.

PyObject *PyType_GetModuleByDef(PyTypeObject *type, struct PyModuleDef *def)
  Retorna valor: Referência emprestada. Parte da ABI Estável desde a versão 3.13.

  Find the first superclass whose module was created from the given `PyModuleDef` def, 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.

  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.

  Adicionado na versão 3.11.

int PyType_GetBaseByToken(PyTypeObject *type, void *token, PyTypeObject **result)
  Parte da ABI Estável desde a versão 3.14.

  Find the first superclass in type’s method resolution order whose `Py_tp_token` token is equal to the given one.

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

  - If not found, set *result to `NULL` and return `0`.

  - On error, set *result to `NULL` and return `-1` with an exception set.

  The result argument may be `NULL`, in which case *result is not set. Use this if you need only the return value.

  The token argument may not be `NULL`.

  Adicionado na versão 3.14.

int PyUnstable_Type_AssignVersionTag(PyTypeObject *type)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  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.

  Adicionado na versão 3.12.

## Creating Heap-Allocated Types

The following functions and structs are used to create heap types.

PyObject *PyType_FromMetaclass(PyTypeObject *metaclass, PyObject *module, PyType_Spec *spec, PyObject *bases)
  Parte da ABI Estável desde a versão 3.12.

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

  The metaclass metaclass is used to construct the resulting type object. When metaclass is `NULL`, the metaclass is derived from bases (or Py_tp_base[s] slots if bases is `NULL`, see below).

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

  The bases argument can be used to specify base classes; it can either be only one class or a tuple of classes. If bases is `NULL`, the Py_tp_bases slot is used instead. If that also is `NULL`, the Py_tp_base slot is used instead. If that also is `NULL`, the new type derives from `object`.

  The module argument can be used to record the module in which the new class is defined. It must be a module object or `NULL`. If not `NULL`, 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 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__()` is not called on the new class (and it must be set to `type.__new__`).

  - `__init__()` is not called on the new class.

  - `__init_subclass__()` is not called on any bases.

  - `__set_name__()` is not called on new descriptors.

  Adicionado na versão 3.12.

PyObject *PyType_FromModuleAndSpec(PyObject *module, PyType_Spec *spec, PyObject *bases)
  Retorna valor: Nova referência. Parte da ABI Estável desde a versão 3.10.

  Equivalent to `PyType_FromMetaclass(NULL, module, spec, bases)`.

  Adicionado na versão 3.9.

  Alterado na versão 3.10: The function now accepts a single class as the bases argument and `NULL` as the `tp_doc` slot.

  Alterado na versão 3.12: 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.

  Alterado na versão 3.14: Creating classes whose metaclass overrides `tp_new` is no longer allowed.

PyObject *PyType_FromSpecWithBases(PyType_Spec *spec, PyObject *bases)
  Retorna valor: Nova referência. Parte da ABI Estável desde a versão 3.3.

  Equivalent to `PyType_FromMetaclass(NULL, NULL, spec, bases)`.

  Adicionado na versão 3.3.

  Alterado na versão 3.12: 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.

  Alterado na versão 3.14: Creating classes whose metaclass overrides `tp_new` is no longer allowed.

PyObject *PyType_FromSpec(PyType_Spec *spec)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Equivalent to `PyType_FromMetaclass(NULL, NULL, spec, NULL)`.

  Alterado na versão 3.12: 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.

  Alterado na versão 3.14: Creating classes whose metaclass overrides `tp_new` is no longer allowed.

int PyType_Freeze(PyTypeObject *type)
  Parte da ABI Estável desde a versão 3.14.

  Make a type immutable: set the `Py_TPFLAGS_IMMUTABLETYPE` flag.

  All base classes of type must be immutable.

  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.

  Adicionado na versão 3.14.

type PyType_Spec
  Parte da ABI Estável (incluindo todos os membros).

  Structure defining a type’s behavior.

  const char *name

    Name of the type, used to set `PyTypeObject.tp_name`.

  int basicsize

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

    If zero, specifies that `tp_basicsize` should be inherited.

    If negative, the absolute value specifies how much space instances of the class need in addition to the superclass. Use `PyObject_GetTypeData()` to get a pointer to subclass-specific memory reserved this way. For negative `basicsize`, Python will insert padding when needed to meet `tp_basicsize`’s alignment requirements.

    Alterado na versão 3.12: Previously, this field could not be negative.

  int itemsize

    Size of one element of a variable-size type, in bytes. Used to set `PyTypeObject.tp_itemsize`. See `tp_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, 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.

  unsigned int flags

    Type flags, used to set `PyTypeObject.tp_flags`.

    If the `Py_TPFLAGS_HEAPTYPE` flag is not set, `PyType_FromSpecWithBases()` sets it automatically.

  PyType_Slot *slots

    Array of `PyType_Slot` structures. Terminated by the special slot value `{0, NULL}`.

    Each slot ID should be specified at most once.

type PyType_Slot
  Parte da ABI Estável (incluindo todos os membros).

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

  int slot

    A slot ID.

    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` to set `PyTypeObject.tp_dealloc`

    - `Py_nb_add` to set `PyNumberMethods.nb_add`

    - `Py_sq_length` to set `PySequenceMethods.sq_length`

    An additional slot is supported that does not correspond to a `PyTypeObject` struct field:

    - `Py_tp_token`

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

    - `tp_weaklistoffset` (use `Py_TPFLAGS_MANAGED_WEAKREF` instead if possible)

    - `tp_dictoffset` (use `Py_TPFLAGS_MANAGED_DICT` instead if possible)

    - `tp_vectorcall_offset` (use `"__vectorcalloffset__"` in PyMemberDef)

    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`.

    Setting `Py_tp_bases` or `Py_tp_base` may be problematic on some platforms. To avoid issues, use the bases argument of `PyType_FromSpecWithBases()` instead.

    Alterado na versão 3.9: Slots in `PyBufferProcs` may be set in the unlimited API.

    Alterado na versão 3.11: `bf_getbuffer` and `bf_releasebuffer` are now available under the limited API.

    Alterado na versão 3.14: The field `tp_vectorcall` can now set using `Py_tp_vectorcall`. See the field’s documentation for details.

  void *pfunc

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

    pfunc values may not be `NULL`, except for the following slots:

    - `Py_tp_doc`

    - `Py_tp_token` (for clarity, prefer `Py_TP_USE_SPEC` rather than `NULL`)

Py_tp_token

  A `slot` that records a static memory layout ID for a class.

  If the `PyType_Spec` of the class 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`.

  Adicionado na versão 3.14.

  Py_TP_USE_SPEC

    Used as a value with `Py_tp_token` to set the token to the class’s `PyType_Spec`. Expands to `NULL`.

    Adicionado na versão 3.14.