Decrement the reference count for object \var{o}. The object may be
\NULL, in which case the macro has no effect; otherwise the effect
is the same as for \cfunction{Py_DECREF()}, except that the argument
- is also set to \NULL. The warning for \cfunction{Py_DECREF()}, does
+ is also set to \NULL. The warning for \cfunction{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 it's reference count.
+ 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.