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from .object cimport PyObject, PyTypeObject, Py_TYPE # legacy imports for re-export
cdef extern from "Python.h":
#####################################################################
# 3. Reference Counts
#####################################################################
# The macros in this section are used for managing reference counts of Python objects.
void Py_INCREF(object o)
# Increment the reference count for object o. The object must not
# be NULL; if you aren't sure that it isn't NULL, use
# Py_XINCREF().
void Py_XINCREF(PyObject* o)
# Increment the reference count for object o. The object may be NULL, in which case the macro has no effect.
void Py_DECREF(object o)
# Decrement the reference count for object o. The object must not
# be NULL; if you aren't sure that it isn't NULL, use
# Py_XDECREF(). If the reference count reaches zero, the object's
# type's deallocation function (which must not be NULL) is
# invoked.
# Warning: The deallocation function can cause arbitrary Python
# code to be invoked (e.g. when a class instance with a __del__()
# method is deallocated). While exceptions in such code are not
# propagated, the executed code has free access to all Python
# global variables. This means that any object that is reachable
# from a global variable should be in a consistent state before
# Py_DECREF() is invoked. For example, code to delete an object
# from a list should copy a reference to the deleted object in a
# temporary variable, update the list data structure, and then
# call Py_DECREF() for the temporary variable.
void Py_XDECREF(PyObject* o)
# Decrement the reference count for object o. The object may be
# NULL, in which case the macro has no effect; otherwise the
# effect is the same as for Py_DECREF(), and the same warning
# applies.
void Py_CLEAR(PyObject* o)
# Decrement the reference count for object o. The object may be
# NULL, in which case the macro has no effect; otherwise the
# effect is the same as for Py_DECREF(), except that the argument
# is also set to NULL. The warning for Py_DECREF() does not apply
# with respect to the object passed because the macro carefully
# uses a temporary variable and sets the argument to NULL before
# decrementing its reference count.
# It is a good idea to use this macro whenever decrementing the
# value of a variable that might be traversed during garbage
# collection.
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