8 .. index:: object: module
10 There are only a few functions special to module objects.
13 .. cvar:: PyTypeObject PyModule_Type
15 .. index:: single: ModuleType (in module types)
17 This instance of :ctype:`PyTypeObject` represents the Python module type. This
18 is exposed to Python programs as ``types.ModuleType``.
21 .. cfunction:: int PyModule_Check(PyObject *p)
23 Return true if *p* is a module object, or a subtype of a module object.
26 .. cfunction:: int PyModule_CheckExact(PyObject *p)
28 Return true if *p* is a module object, but not a subtype of
29 :cdata:`PyModule_Type`.
32 .. cfunction:: PyObject* PyModule_New(const char *name)
35 single: __name__ (module attribute)
36 single: __doc__ (module attribute)
37 single: __file__ (module attribute)
39 Return a new module object with the :attr:`__name__` attribute set to *name*.
40 Only the module's :attr:`__doc__` and :attr:`__name__` attributes are filled in;
41 the caller is responsible for providing a :attr:`__file__` attribute.
44 .. cfunction:: PyObject* PyModule_GetDict(PyObject *module)
46 .. index:: single: __dict__ (module attribute)
48 Return the dictionary object that implements *module*'s namespace; this object
49 is the same as the :attr:`__dict__` attribute of the module object. This
50 function never fails. It is recommended extensions use other
51 :cfunc:`PyModule_\*` and :cfunc:`PyObject_\*` functions rather than directly
52 manipulate a module's :attr:`__dict__`.
55 .. cfunction:: char* PyModule_GetName(PyObject *module)
58 single: __name__ (module attribute)
59 single: SystemError (built-in exception)
61 Return *module*'s :attr:`__name__` value. If the module does not provide one,
62 or if it is not a string, :exc:`SystemError` is raised and *NULL* is returned.
65 .. cfunction:: char* PyModule_GetFilename(PyObject *module)
68 single: __file__ (module attribute)
69 single: SystemError (built-in exception)
71 Return the name of the file from which *module* was loaded using *module*'s
72 :attr:`__file__` attribute. If this is not defined, or if it is not a string,
73 raise :exc:`SystemError` and return *NULL*.
76 .. cfunction:: void* PyModule_GetState(PyObject *module)
78 Return the "state" of the module, that is, a pointer to the block of memory
79 allocated at module creation time, or *NULL*. See
80 :cmember:`PyModuleDef.m_size`.
83 .. cfunction:: PyModuleDef* PyModule_GetDef(PyObject *module)
85 Return a pointer to the :ctype:`PyModuleDef` struct from which the module was
86 created, or *NULL* if the module wasn't created with
87 :cfunc:`PyModule_Create`.
90 Initializing C modules
91 ^^^^^^^^^^^^^^^^^^^^^^
93 These functions are usually used in the module initialization function.
95 .. cfunction:: PyObject* PyModule_Create(PyModuleDef *module)
97 Create a new module object, given the definition in *module*. This behaves
98 like :cfunc:`PyModule_Create2` with *module_api_version* set to
99 :const:`PYTHON_API_VERSION`.
102 .. cfunction:: PyObject* PyModule_Create2(PyModuleDef *module, int module_api_version)
104 Create a new module object, given the definition in *module*, assuming the
105 API version *module_api_version*. If that version does not match the version
106 of the running interpreter, a :exc:`RuntimeWarning` is emitted.
110 Most uses of this function should be using :cfunc:`PyModule_Create`
111 instead; only use this if you are sure you need it.
114 .. ctype:: PyModuleDef
116 This struct holds all information that is needed to create a module object.
117 There is usually only one static variable of that type for each module, which
118 is statically initialized and then passed to :cfunc:`PyModule_Create` in the
119 module initialization function.
121 .. cmember:: PyModuleDef_Base m_base
123 Always initialize this member to :const:`PyModuleDef_HEAD_INIT`.
125 .. cmember:: char* m_name
127 Name for the new module.
129 .. cmember:: char* m_doc
131 Docstring for the module; usually a docstring variable created with
132 :cfunc:`PyDoc_STRVAR` is used.
134 .. cmember:: Py_ssize_t m_size
136 If the module object needs additional memory, this should be set to the
137 number of bytes to allocate; a pointer to the block of memory can be
138 retrieved with :cfunc:`PyModule_GetState`. If no memory is needed, set
141 This memory should be used, rather than static globals, to hold per-module
142 state, since it is then safe for use in multiple sub-interpreters. It is
143 freed when the module object is deallocated, after the :cmember:`m_free`
144 function has been called, if present.
146 .. cmember:: PyMethodDef* m_methods
148 A pointer to a table of module-level functions, described by
149 :ctype:`PyMethodDef` values. Can be *NULL* if no functions are present.
151 .. cmember:: inquiry m_reload
153 Currently unused, should be *NULL*.
155 .. cmember:: traverseproc m_traverse
157 A traversal function to call during GC traversal of the module object, or
158 *NULL* if not needed.
160 .. cmember:: inquiry m_clear
162 A clear function to call during GC clearing of the module object, or
163 *NULL* if not needed.
165 .. cmember:: freefunc m_free
167 A function to call during deallocation of the module object, or *NULL* if
171 .. cfunction:: int PyModule_AddObject(PyObject *module, const char *name, PyObject *value)
173 Add an object to *module* as *name*. This is a convenience function which can
174 be used from the module's initialization function. This steals a reference to
175 *value*. Return ``-1`` on error, ``0`` on success.
178 .. cfunction:: int PyModule_AddIntConstant(PyObject *module, const char *name, long value)
180 Add an integer constant to *module* as *name*. This convenience function can be
181 used from the module's initialization function. Return ``-1`` on error, ``0`` on
185 .. cfunction:: int PyModule_AddStringConstant(PyObject *module, const char *name, const char *value)
187 Add a string constant to *module* as *name*. This convenience function can be
188 used from the module's initialization function. The string *value* must be
189 null-terminated. Return ``-1`` on error, ``0`` on success.
192 .. cfunction:: int PyModule_AddIntMacro(PyObject *module, macro)
194 Add an int constant to *module*. The name and the value are taken from
195 *macro*. For example ``PyModule_AddConstant(module, AF_INET)`` adds the int
196 constant *AF_INET* with the value of *AF_INET* to *module*.
197 Return ``-1`` on error, ``0`` on success.
200 .. cfunction:: int PyModule_AddStringMacro(PyObject *module, macro)
202 Add a string constant to *module*.