56 lines
2.3 KiB
C
56 lines
2.3 KiB
C
/* GNU Objective C Runtime nil receiver function
|
|
Copyright (C) 1993, 1995, 1996, 2002 Free Software Foundation, Inc.
|
|
Contributed by Kresten Krab Thorup
|
|
|
|
This file is part of GCC.
|
|
|
|
GCC is free software; you can redistribute it and/or modify it under the
|
|
terms of the GNU General Public License as published by the Free Software
|
|
Foundation; either version 2, or (at your option) any later version.
|
|
|
|
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
|
details.
|
|
|
|
You should have received a copy of the GNU General Public License along with
|
|
GCC; see the file COPYING. If not, write to the Free Software
|
|
Foundation, 51 Franklin Street, Fifth Floor,
|
|
Boston, MA 02110-1301, USA. */
|
|
|
|
/* As a special exception, if you link this library with files compiled with
|
|
GCC to produce an executable, this does not cause the resulting executable
|
|
to be covered by the GNU General Public License. This exception does not
|
|
however invalidate any other reasons why the executable file might be
|
|
covered by the GNU General Public License. */
|
|
|
|
/* This is the nil method, the function that is called when the receiver
|
|
of a method is nil */
|
|
|
|
#include "objc/runtime.h"
|
|
|
|
/* When the receiver of a method invocation is nil, the runtime
|
|
returns nil_method() as the method implementation. This function
|
|
will be casted to whatever function was supposed to be executed to
|
|
execute that method (that function will take an id, followed by a
|
|
SEL, followed by who knows what arguments, depends on the method),
|
|
and executed.
|
|
|
|
For this reason, nil_method() should be a function which can be
|
|
called in place of any function taking an 'id' argument followed by
|
|
a 'SEL' argument, followed by zero, or one, or any number of
|
|
arguments (both a fixed number, or a variable number !).
|
|
|
|
There is no "proper" implementation of such a nil_method function
|
|
in C, however in all existing implementations it does not matter
|
|
when extra arguments are present, so we can simply create a function
|
|
taking a receiver and a selector, and all other arguments will be
|
|
ignored. :-)
|
|
*/
|
|
|
|
id
|
|
nil_method (id receiver, SEL op __attribute__ ((__unused__)))
|
|
{
|
|
return receiver;
|
|
}
|