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Diffstat (limited to 'Doc/c-api/module.rst')
| -rw-r--r-- | Doc/c-api/module.rst | 92 |
1 files changed, 66 insertions, 26 deletions
diff --git a/Doc/c-api/module.rst b/Doc/c-api/module.rst index 985a347..df9301f 100644 --- a/Doc/c-api/module.rst +++ b/Doc/c-api/module.rst @@ -7,8 +7,6 @@ Module Objects .. index:: object: module -There are only a few functions special to module objects. - .. c:var:: PyTypeObject PyModule_Type @@ -109,6 +107,14 @@ There are only a few functions special to module objects. unencodable filenames, use :c:func:`PyModule_GetFilenameObject` instead. +Per-interpreter module state +^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Single-phase initialization creates singleton modules that can store additional +information as part of the interpreter, allow that state to be retrieved later +with only a reference to the module definition, rather than to the module +itself. + .. c:function:: void* PyModule_GetState(PyObject *module) Return the "state" of the module, that is, a pointer to the block of memory @@ -146,27 +152,6 @@ There are only a few functions special to module objects. Initializing C modules ^^^^^^^^^^^^^^^^^^^^^^ -These functions are usually used in the module initialization function. - -.. c:function:: PyObject* PyModule_Create(PyModuleDef *module) - - Create a new module object, given the definition in *module*. This behaves - like :c:func:`PyModule_Create2` with *module_api_version* set to - :const:`PYTHON_API_VERSION`. - - -.. c:function:: PyObject* PyModule_Create2(PyModuleDef *module, int module_api_version) - - Create a new module object, given the definition in *module*, assuming the - API version *module_api_version*. If that version does not match the version - of the running interpreter, a :exc:`RuntimeWarning` is emitted. - - .. note:: - - Most uses of this function should be using :c:func:`PyModule_Create` - instead; only use this if you are sure you need it. - - .. c:type:: PyModuleDef This struct holds all information that is needed to create a module object. @@ -210,9 +195,10 @@ These functions are usually used in the module initialization function. A pointer to a table of module-level functions, described by :c:type:`PyMethodDef` values. Can be *NULL* if no functions are present. - .. c:member:: inquiry m_reload + .. c:member:: PyModuleDef_Slot* m_slots - Currently unused, should be *NULL*. + An array of slot definitions for multi-phase initialization, terminated by + a *NULL* entry. .. c:member:: traverseproc m_traverse @@ -229,6 +215,61 @@ These functions are usually used in the module initialization function. A function to call during deallocation of the module object, or *NULL* if not needed. +The module initialization function may create and return the module object +directly. This is referred to as "single-phase initialization", and uses one +of the following two module creation functions: + +.. c:function:: PyObject* PyModule_Create(PyModuleDef *module) + + Create a new module object, given the definition in *module*. This behaves + like :c:func:`PyModule_Create2` with *module_api_version* set to + :const:`PYTHON_API_VERSION`. + + +.. c:function:: PyObject* PyModule_Create2(PyModuleDef *module, int module_api_version) + + Create a new module object, given the definition in *module*, assuming the + API version *module_api_version*. If that version does not match the version + of the running interpreter, a :exc:`RuntimeWarning` is emitted. + + .. note:: + + Most uses of this function should be using :c:func:`PyModule_Create` + instead; only use this if you are sure you need it. + + +Alternatively, the module initialization function may instead return a +:c:type:`PyModuleDef` instance with a non-empty ``m_slots`` array. This is +referred to as "multi-phase initialization", and ``PyModuleDef`` instance +should be initialized with the following function: + +.. c:function:: PyObject* PyModuleDef_Init(PyModuleDef *module) + + Ensures a module definition is a properly initialized Python object that + correctly reports its type and reference count. + +.. XXX (ncoghlan): It's not clear if it makes sense to document PyModule_ExecDef + PyModule_FromDefAndSpec or PyModule_FromDefAndSpec2 here, as end user code + generally shouldn't be calling those. + +The module initialization function (if using single phase initialization) or +a function called from a module execution slot (if using multiphase +initialization), can use the following functions to help initialize the module +state: + +.. c:function:: int PyModule_SetDocString(PyObject *module, const char *docstring) + + Set the docstring for *module* to *docstring*. Return ``-1`` on error, ``0`` + on success. + +.. c:function:: int PyModule_AddFunctions(PyObject *module, PyMethodDef *functions) + + Add the functions from the ``NULL`` terminated *functions* array to *module*. + Refer to the :c:type:`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). + .. c:function:: int PyModule_AddObject(PyObject *module, const char *name, PyObject *value) @@ -236,7 +277,6 @@ These functions are usually used in the module initialization function. be used from the module's initialization function. This steals a reference to *value*. Return ``-1`` on error, ``0`` on success. - .. c:function:: int PyModule_AddIntConstant(PyObject *module, const char *name, long value) Add an integer constant to *module* as *name*. This convenience function can be |