[Main page] [Overview]     /efun /set_this_object

---

SYNOPSIS
void set_this_object(object object_to_pretend_to_be);

DESCRIPTION
This is a privileged function, only to be used in the master
object or in the simul_efun object.

It changes the result of this_object() in the using function,
and the result of previous_object() in functions called in
other objects by call_other()/apply()/funcall(). Its effect will
remain till there is a return of an external function call, or
another call of set_this_object(). While executing code in the
master object's program or the primary simul_efun object's
program, set_this_object() is granted even if this_object() is
altered by set_this_object(). This does not apply to functions
inherited from other programs.

Use it with extreme care to avoid inconsistencies. After a
call of set_this_object(), some LPC-constructs might behave in
an odd manner, or even crash the system. In particular, using
global variables or calling local functions (except by
call_other) is illegal and actively prevented.

Allowed are call_other(), map functions, access of local variables
(which might hold array pointers to a global array), simple arithmetic
and the assignment operators.

BUGS
It is currently not possible to directly restore the original
current object. So instead of writing

object me = this_object();
set_this_object(that);
<some code>
set_this_object(me);
<more code>

one has to use a workaround:

private void doit (object that) {
set_this_object(that);
<some code>
}

funcall(#'doit, that);
<more code>

Some people would consider this a feature.


HISTORY
LDMud 3.2.10 actively prevents references to global variables
and function calls by address while set_this_object() is in
effect.

SEE ALSO
this_object(E), set_this_player(E)