Objetos módulo

PyTypeObject PyModule_Type
Part of the Stable ABI.

Esta instancia de PyTypeObject representa el tipo de módulo Python. Esto está expuesto a los programas de Python como types.ModuleType.

int PyModule_Check(PyObject *p)

Retorna verdadero si p es un objeto de módulo o un subtipo de un objeto de módulo. Esta función siempre finaliza con éxito.

int PyModule_CheckExact(PyObject *p)

Retorna verdadero si p es un objeto módulo, pero no un subtipo de PyModule_Type. Esta función siempre finaliza con éxito.

PyObject *PyModule_NewObject(PyObject *name)
Return value: New reference. Part of the Stable ABI since version 3.7.

Return a new module object with module.__name__ set to name. The module’s __name__, __doc__, __package__ and __loader__ attributes are filled in (all but __name__ are set to None). The caller is responsible for setting a __file__ attribute.

Return NULL with an exception set on error.

Added in version 3.3.

Distinto en la versión 3.4: __package__ and __loader__ are now set to None.

PyObject *PyModule_New(const char *name)
Return value: New reference. Part of the Stable ABI.

Similar a PyModule_NewObject(), pero el nombre es una cadena de caracteres codificada UTF-8 en lugar de un objeto Unicode.

PyObject *PyModule_GetDict(PyObject *module)
Return value: Borrowed reference. Part of the Stable ABI.

Retorna el objeto del diccionario que implementa el espacio de nombres de module; este objeto es el mismo que el atributo __dict__ del objeto módulo. Si module no es un objeto módulo (o un subtipo de un objeto de módulo), se lanza SystemError y se retorna NULL.

It is recommended extensions use other PyModule_* and PyObject_* functions rather than directly manipulate a module’s __dict__.

PyObject *PyModule_GetNameObject(PyObject *module)
Return value: New reference. Part of the Stable ABI since version 3.7.

Return module’s __name__ value. If the module does not provide one, or if it is not a string, SystemError is raised and NULL is returned.

Added in version 3.3.

const char *PyModule_GetName(PyObject *module)
Part of the Stable ABI.

Similar a PyModule_GetNameObject() pero retorna el nombre codificado a 'utf-8'.

void *PyModule_GetState(PyObject *module)
Part of the Stable ABI.

Retorna el «estado» del módulo, es decir, un puntero al bloque de memoria asignado en el momento de la creación del módulo, o NULL. Ver PyModuleDef.m_size.

PyModuleDef *PyModule_GetDef(PyObject *module)
Part of the Stable ABI.

Retorna un puntero a la estructura PyModuleDef a partir de la cual se creó el módulo, o NULL si el módulo no se creó a partir de una definición.

PyObject *PyModule_GetFilenameObject(PyObject *module)
Return value: New reference. Part of the Stable ABI.

Return the name of the file from which module was loaded using module’s __file__ attribute. If this is not defined, or if it is not a string, raise SystemError and return NULL; otherwise return a reference to a Unicode object.

Added in version 3.2.

const char *PyModule_GetFilename(PyObject *module)
Part of the Stable ABI.

Similar a PyModule_GetFilenameObject() pero retorna el nombre de archivo codificado a “utf-8”.

Obsoleto desde la versión 3.2: PyModule_GetFilename() raises UnicodeEncodeError on unencodable filenames, use PyModule_GetFilenameObject() instead.

Module definitions

The functions in the previous section work on any module object, including modules imported from Python code.

Modules defined using the C API typically use a module definition, PyModuleDef – a statically allocated, constant “description» of how a module should be created.

The definition is usually used to define an extension’s “main” module object (see Defining extension modules for details). It is also used to create extension modules dynamically.

Unlike PyModule_New(), the definition allows management of module state – a piece of memory that is allocated and cleared together with the module object. Unlike the module’s Python attributes, Python code cannot replace or delete data stored in module state.

type PyModuleDef
Part of the Stable ABI (including all members).

The module definition struct, which holds all information needed to create a module object. This structure must be statically allocated (or be otherwise guaranteed to be valid while any modules created from it exist). Usually, there is only one variable of this type for each extension module.

PyModuleDef_Base m_base

Always initialize this member to PyModuleDef_HEAD_INIT.

const char *m_name

Nombre para el nuevo módulo.

const char *m_doc

Docstring para el módulo; por lo general, se usa una variable docstring creada con PyDoc_STRVAR.

Py_ssize_t m_size

El estado del módulo se puede mantener en un área de memoria por módulo que se puede recuperar con PyModule_GetState(), en lugar de en globales estáticos. Esto hace que los módulos sean seguros para su uso en múltiples sub-interpretadores.

This memory area is allocated based on m_size on module creation, and freed when the module object is deallocated, after the m_free function has been called, if present.

Setting it to a non-negative value means that the module can be re-initialized and specifies the additional amount of memory it requires for its state.

Setting m_size to -1 means that the module does not support sub-interpreters, because it has global state. Negative m_size is only allowed when using legacy single-phase initialization or when creating modules dynamically.

Ver PEP 3121 para más detalles.

PyMethodDef *m_methods

Un puntero a una tabla de funciones de nivel de módulo, descrito por valores PyMethodDef. Puede ser NULL si no hay funciones presentes.

PyModuleDef_Slot *m_slots

An array of slot definitions for multi-phase initialization, terminated by a {0, NULL} entry. When using legacy single-phase initialization, m_slots must be NULL.

Distinto en la versión 3.5: Antes de la versión 3.5, este miembro siempre estaba configurado en NULL y se definía como:

inquiry m_reload
traverseproc m_traverse

Una función transversal para llamar durante el recorrido GC del objeto del módulo, o NULL si no es necesario.

This function is not called if the module state was requested but is not allocated yet. This is the case immediately after the module is created and before the module is executed (Py_mod_exec function). More precisely, this function is not called if m_size is greater than 0 and the module state (as returned by PyModule_GetState()) is NULL.

Distinto en la versión 3.9: Ya no se llama antes de que se asigne el estado del módulo.

inquiry m_clear

Una función clara para llamar durante la limpieza GC del objeto del módulo, o NULL si no es necesario.

This function is not called if the module state was requested but is not allocated yet. This is the case immediately after the module is created and before the module is executed (Py_mod_exec function). More precisely, this function is not called if m_size is greater than 0 and the module state (as returned by PyModule_GetState()) is NULL.

Tal como PyTypeObject.tp_clear, esta función no siempre es llamada antes de la designación de un módulo. Por ejemplo, cuando el recuento de referencias está listo para determinar que un objeto no se usa más, la recolección de basura cíclica no se involucra y se llama a m_free directamente.

Distinto en la versión 3.9: Ya no se llama antes de que se asigne el estado del módulo.

freefunc m_free

Una función para llamar durante la desasignación del objeto del módulo, o NULL si no es necesario.

This function is not called if the module state was requested but is not allocated yet. This is the case immediately after the module is created and before the module is executed (Py_mod_exec function). More precisely, this function is not called if m_size is greater than 0 and the module state (as returned by PyModule_GetState()) is NULL.

Distinto en la versión 3.9: Ya no se llama antes de que se asigne el estado del módulo.

Module slots

type PyModuleDef_Slot
int slot

Una ranura ID, elegida entre los valores disponibles que se explican a continuación.

void *value

Valor de la ranura, cuyo significado depende de la ID de la ranura.

Added in version 3.5.

Los tipos de ranura disponibles son:

Py_mod_create

Especifica una función que se llama para crear el objeto del módulo en sí. El puntero value de este espacio debe apuntar a una función de la firma:

PyObject *create_module(PyObject *spec, PyModuleDef *def)

La función recibe una instancia de ModuleSpec, como se define en PEP 451, y la definición del módulo. Debería retornar un nuevo objeto de módulo, o establecer un error y retornar NULL.

Esta función debe mantenerse mínima. En particular, no debería llamar a código arbitrario de Python, ya que intentar importar el mismo módulo nuevamente puede dar como resultado un bucle infinito.

Múltiples ranuras Py_mod_create no pueden especificarse en una definición de módulo.

Si no se especifica Py_mod_create, la maquinaria de importación creará un objeto de módulo normal usando PyModule_New(). El nombre se toma de spec, no de la definición, para permitir que los módulos de extensión se ajusten dinámicamente a su lugar en la jerarquía de módulos y se importen bajo diferentes nombres a través de enlaces simbólicos, todo mientras se comparte una definición de módulo único.

No es necesario que el objeto retornado sea una instancia de PyModule_Type. Se puede usar cualquier tipo, siempre que admita la configuración y la obtención de atributos relacionados con la importación. Sin embargo, solo se pueden retornar instancias PyModule_Type si el PyModuleDef no tiene NULL m_traverse, m_clear, m_free; m_size distinto de cero; o ranuras que no sean Py_mod_create.

Py_mod_exec

Especifica una función que se llama para ejecutar (execute) el módulo. Esto es equivalente a ejecutar el código de un módulo Python: por lo general, esta función agrega clases y constantes al módulo. La firma de la función es:

int exec_module(PyObject *module)

Si se especifican varias ranuras Py_mod_exec, se procesan en el orden en que aparecen en el arreglo m_slots.

Py_mod_multiple_interpreters

Specifies one of the following values:

Py_MOD_MULTIPLE_INTERPRETERS_NOT_SUPPORTED

The module does not support being imported in subinterpreters.

Py_MOD_MULTIPLE_INTERPRETERS_SUPPORTED

The module supports being imported in subinterpreters, but only when they share the main interpreter’s GIL. (See Aislamiento de módulos de extensión.)

Py_MOD_PER_INTERPRETER_GIL_SUPPORTED

The module supports being imported in subinterpreters, even when they have their own GIL. (See Aislamiento de módulos de extensión.)

This slot determines whether or not importing this module in a subinterpreter will fail.

Multiple Py_mod_multiple_interpreters slots may not be specified in one module definition.

If Py_mod_multiple_interpreters is not specified, the import machinery defaults to Py_MOD_MULTIPLE_INTERPRETERS_SUPPORTED.

Added in version 3.12.

Py_mod_gil

Specifies one of the following values:

Py_MOD_GIL_USED

The module depends on the presence of the global interpreter lock (GIL), and may access global state without synchronization.

Py_MOD_GIL_NOT_USED

The module is safe to run without an active GIL.

This slot is ignored by Python builds not configured with --disable-gil. Otherwise, it determines whether or not importing this module will cause the GIL to be automatically enabled. See Free-threaded CPython for more detail.

Multiple Py_mod_gil slots may not be specified in one module definition.

If Py_mod_gil is not specified, the import machinery defaults to Py_MOD_GIL_USED.

Added in version 3.13.

Creating extension modules dynamically

The following functions may be used to create a module outside of an extension’s initialization function. They are also used in single-phase initialization.

PyObject *PyModule_Create(PyModuleDef *def)
Return value: New reference.

Create a new module object, given the definition in def. This is a macro that calls PyModule_Create2() with module_api_version set to PYTHON_API_VERSION, or to PYTHON_ABI_VERSION if using the limited API.

PyObject *PyModule_Create2(PyModuleDef *def, int module_api_version)
Return value: New reference. Part of the Stable ABI.

Crea un nuevo objeto de módulo, dada la definición en def, asumiendo la versión de API module_api_version. Si esa versión no coincide con la versión del intérprete en ejecución, se emite un RuntimeWarning.

Return NULL with an exception set on error.

This function does not support slots. The m_slots member of def must be NULL.

Nota

La mayoría de los usos de esta función deberían usar PyModule_Create() en su lugar; solo use esto si está seguro de que lo necesita.

PyObject *PyModule_FromDefAndSpec(PyModuleDef *def, PyObject *spec)
Return value: New reference.

This macro calls PyModule_FromDefAndSpec2() with module_api_version set to PYTHON_API_VERSION, or to PYTHON_ABI_VERSION if using the limited API.

Added in version 3.5.

PyObject *PyModule_FromDefAndSpec2(PyModuleDef *def, PyObject *spec, int module_api_version)
Return value: New reference. Part of the Stable ABI since version 3.7.

Create a new module object, given the definition in def and the ModuleSpec spec, assuming the API version module_api_version. If that version does not match the version of the running interpreter, a RuntimeWarning is emitted.

Return NULL with an exception set on error.

Note that this does not process execution slots (Py_mod_exec). Both PyModule_FromDefAndSpec and PyModule_ExecDef must be called to fully initialize a module.

Nota

La mayoría de los usos de esta función deberían usar PyModule_FromDefAndSpec() en su lugar; solo use esto si está seguro de que lo necesita.

Added in version 3.5.

int PyModule_ExecDef(PyObject *module, PyModuleDef *def)
Part of the Stable ABI since version 3.7.

Procesa cualquier ranura de ejecución (Py_mod_exec) dado en def.

Added in version 3.5.

PYTHON_API_VERSION

The C API version. Defined for backwards compatibility.

Currently, this constant is not updated in new Python versions, and is not useful for versioning. This may change in the future.

PYTHON_ABI_VERSION

Defined as 3 for backwards compatibility.

Currently, this constant is not updated in new Python versions, and is not useful for versioning. This may change in the future.

Funciones de soporte

The following functions are provided to help initialize a module state. They are intended for a module’s execution slots (Py_mod_exec), the initialization function for legacy single-phase initialization, or code that creates modules dynamically.

int PyModule_AddObjectRef(PyObject *module, const char *name, PyObject *value)
Part of the Stable ABI since version 3.10.

Agrega un objeto a module como name. Esta es una función de conveniencia que se puede usar desde la función de inicialización del módulo.

En caso de éxito, retorna 0. En caso de error, lanza una excepción y retorna -1.

Ejemplo de uso

static int
add_spam(PyObject *module, int value)
{
    PyObject *obj = PyLong_FromLong(value);
    if (obj == NULL) {
        return -1;
    }
    int res = PyModule_AddObjectRef(module, "spam", obj);
    Py_DECREF(obj);
    return res;
 }

To be convenient, the function accepts NULL value with an exception set. In this case, return -1 and just leave the raised exception unchanged.

El ejemplo puede también ser escrito sin verificar explicitamente si obj es NULL:

static int
add_spam(PyObject *module, int value)
{
    PyObject *obj = PyLong_FromLong(value);
    int res = PyModule_AddObjectRef(module, "spam", obj);
    Py_XDECREF(obj);
    return res;
 }

Note que Py_XDECREF() debería ser usado en vez de Py_DECREF() en este caso, ya que obj puede ser NULL.

The number of different name strings passed to this function should be kept small, usually by only using statically allocated strings as name. For names that aren’t known at compile time, prefer calling PyUnicode_FromString() and PyObject_SetAttr() directly. For more details, see PyUnicode_InternFromString(), which may be used internally to create a key object.

Added in version 3.10.

int PyModule_Add(PyObject *module, const char *name, PyObject *value)
Part of the Stable ABI since version 3.13.

Similar to PyModule_AddObjectRef(), but «steals» a reference to value. It can be called with a result of function that returns a new reference without bothering to check its result or even saving it to a variable.

Ejemplo de uso

if (PyModule_Add(module, "spam", PyBytes_FromString(value)) < 0) {
    goto error;
}

Added in version 3.13.

int PyModule_AddObject(PyObject *module, const char *name, PyObject *value)
Part of the Stable ABI.

Similar a PyModule_AddObjectRef(), pero roba una referencia a value en caso de éxito (en este caso retorna 0).

The new PyModule_Add() or PyModule_AddObjectRef() functions are recommended, since it is easy to introduce reference leaks by misusing the PyModule_AddObject() function.

Nota

Unlike other functions that steal references, PyModule_AddObject() only releases the reference to value on success.

This means that its return value must be checked, and calling code must Py_XDECREF() value manually on error.

Ejemplo de uso

PyObject *obj = PyBytes_FromString(value);
if (PyModule_AddObject(module, "spam", obj) < 0) {
    // If 'obj' is not NULL and PyModule_AddObject() failed,
    // 'obj' strong reference must be deleted with Py_XDECREF().
    // If 'obj' is NULL, Py_XDECREF() does nothing.
    Py_XDECREF(obj);
    goto error;
}
// PyModule_AddObject() stole a reference to obj:
// Py_XDECREF(obj) is not needed here.

Obsoleto desde la versión 3.13: PyModule_AddObject() is soft deprecated.

int PyModule_AddIntConstant(PyObject *module, const char *name, long value)
Part of the Stable ABI.

Add an integer constant to module as name. This convenience function can be used from the module’s initialization function. Return -1 with an exception set on error, 0 on success.

This is a convenience function that calls PyLong_FromLong() and PyModule_AddObjectRef(); see their documentation for details.

int PyModule_AddStringConstant(PyObject *module, const char *name, const char *value)
Part of the Stable ABI.

Add a string constant to module as name. This convenience function can be used from the module’s initialization function. The string value must be NULL-terminated. Return -1 with an exception set on error, 0 on success.

This is a convenience function that calls PyUnicode_InternFromString() and PyModule_AddObjectRef(); see their documentation for details.

PyModule_AddIntMacro(module, macro)

Add an int constant to module. The name and the value are taken from macro. For example PyModule_AddIntMacro(module, AF_INET) adds the int constant AF_INET with the value of AF_INET to module. Return -1 with an exception set on error, 0 on success.

PyModule_AddStringMacro(module, macro)

Agrega una constante de cadena de caracteres a module.

int PyModule_AddType(PyObject *module, PyTypeObject *type)
Part of the Stable ABI since version 3.10.

Add a type object to module. The type object is finalized by calling internally PyType_Ready(). The name of the type object is taken from the last component of tp_name after dot. Return -1 with an exception set on error, 0 on success.

Added in version 3.9.

int PyModule_AddFunctions(PyObject *module, PyMethodDef *functions)
Part of the Stable ABI since version 3.7.

Add the functions from the NULL terminated functions array to module. Refer to the PyMethodDef documentation for details on individual entries (due to the lack of a shared module namespace, module level «functions» implemented in C typically receive the module as their first parameter, making them similar to instance methods on Python classes).

This function is called automatically when creating a module from PyModuleDef (such as when using Multi-phase initialization, PyModule_Create, or PyModule_FromDefAndSpec). Some module authors may prefer defining functions in multiple PyMethodDef arrays; in that case they should call this function directly.

Added in version 3.5.

int PyModule_SetDocString(PyObject *module, const char *docstring)
Part of the Stable ABI since version 3.7.

Set the docstring for module to docstring. This function is called automatically when creating a module from PyModuleDef (such as when using Multi-phase initialization, PyModule_Create, or PyModule_FromDefAndSpec).

Added in version 3.5.

int PyUnstable_Module_SetGIL(PyObject *module, void *gil)
This is Unstable API. It may change without warning in minor releases.

Indicate that module does or does not support running without the global interpreter lock (GIL), using one of the values from Py_mod_gil. It must be called during module’s initialization function when using Legacy single-phase initialization. If this function is not called during module initialization, the import machinery assumes the module does not support running without the GIL. This function is only available in Python builds configured with --disable-gil. Return -1 with an exception set on error, 0 on success.

Added in version 3.13.

Module lookup (single-phase initialization)

The legacy single-phase initialization initialization scheme creates singleton modules that can be looked up in the context of the current interpreter. This allows the module object to be retrieved later with only a reference to the module definition.

Estas funciones no funcionarán en módulos creados mediante la inicialización de múltiples fases, ya que se pueden crear múltiples módulos de este tipo desde una sola definición.

PyObject *PyState_FindModule(PyModuleDef *def)
Return value: Borrowed reference. Part of the Stable ABI.

Retorna el objeto módulo que se creó a partir de def para el intérprete actual. Este método requiere que el objeto módulo se haya adjuntado al estado del intérprete con PyState_AddModule() de antemano. En caso de que el objeto módulo correspondiente no se encuentre o no se haya adjuntado al estado del intérprete, retornará NULL.

int PyState_AddModule(PyObject *module, PyModuleDef *def)
Part of the Stable ABI since version 3.3.

Adjunta el objeto del módulo pasado a la función al estado del intérprete. Esto permite que se pueda acceder al objeto del módulo a través de PyState_FindModule().

Solo es efectivo en módulos creados con la inicialización monofásica.

Python calls PyState_AddModule automatically after importing a module that uses single-phase initialization, so it is unnecessary (but harmless) to call it from module initialization code. An explicit call is needed only if the module’s own init code subsequently calls PyState_FindModule. The function is mainly intended for implementing alternative import mechanisms (either by calling it directly, or by referring to its implementation for details of the required state updates).

If a module was attached previously using the same def, it is replaced by the new module.

The caller must have an attached thread state.

Return -1 with an exception set on error, 0 on success.

Added in version 3.3.

int PyState_RemoveModule(PyModuleDef *def)
Part of the Stable ABI since version 3.3.

Removes the module object created from def from the interpreter state. Return -1 with an exception set on error, 0 on success.

The caller must have an attached thread state.

Added in version 3.3.