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GeezerVison is showing docs.python.org — Allocating Objects on the Heap

Allocating Objects on the Heap¶

PyObject *_PyObject_New(PyTypeObject *type)¶
Return value: New reference.
PyVarObject *_PyObject_NewVar(PyTypeObject *type, Py_ssize_t size)¶
Return value: New reference.
PyObject *PyObject_Init(PyObject *op, PyTypeObject *type)¶
Return value: Borrowed reference. Part of the Stable ABI.

Initialize a newly allocated object op with its type and initial reference. Returns the initialized object. Other fields of the object are not affected.

PyVarObject *PyObject_InitVar(PyVarObject *op, PyTypeObject *type, Py_ssize_t size)¶
Return value: Borrowed reference. Part of the Stable ABI.

This does everything PyObject_Init() does, and also initializes the length information for a variable-size object.

PyObject_New(TYPE, typeobj)¶

Allocate a new Python object using the C structure type TYPE and the Python type object typeobj (PyTypeObject*). Fields not defined by the Python object header are not initialized. The caller will own the only reference to the object (i.e. its reference count will be one). The size of the memory allocation is determined from the tp_basicsize field of the type object.

Note that this function is unsuitable if typeobj has Py_TPFLAGS_HAVE_GC set. For such objects, use PyObject_GC_New() instead.

PyObject_NewVar(TYPE, typeobj, size)¶

Allocate a new Python object using the C structure type TYPE and the Python type object typeobj (PyTypeObject*). Fields not defined by the Python object header are not initialized. The allocated memory allows for the TYPE structure plus size (Py_ssize_t) fields of the size given by the tp_itemsize field of typeobj. This is useful for implementing objects like tuples, which are able to determine their size at construction time. Embedding the array of fields into the same allocation decreases the number of allocations, improving the memory management efficiency.

Note that this function is unsuitable if typeobj has Py_TPFLAGS_HAVE_GC set. For such objects, use PyObject_GC_NewVar() instead.

void PyObject_Del(void *op)¶

Releases memory allocated to an object using PyObject_New or PyObject_NewVar. This is normally called from the tp_dealloc handler specified in the object’s type. The fields of the object should not be accessed after this call as the memory is no longer a valid Python object.

PyObject _Py_NoneStruct¶

Object which is visible in Python as None. This should only be accessed using the Py_None macro, which evaluates to a pointer to this object.

See also

PyModule_Create()

To allocate and create extension modules.

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