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In BS, pg 164, 5.5.6 it states:

	The assignment to "this" [in a constructor function] informs
	the compiler that the programmer has taken control and that the
	default mechanism for allocating storage should not be used.

With this in mind my questions are:

(1) Does the variable 'this' have to be set in the constructor
    function or can it be set in a subroutine that is called from
    a constructor?

(2) If a member function (called from within the constructor) sets
    the value of 'this', does the compiler still understand that
    "the programmer has taken control"?

(3) Can a "friend" function access (get or set) the value of 'this'?

After testing several examples I learned the answers to questions
1 and 2:

(1) Only a constructor can set the value 'this'.
(2) If a member method attempts to change the value of 'this', an
    error occures which says something to the effect of:
	'You can't modify read-only variable $this'

But the answer to question #3, is not clear.  Although I know
(intuitively) the answer must be that non-member functions can't
access 'this'.  The error message that I got didn't make it
clear to me.

To answer question #3, I tried the following example.

====================  OUTPUT from compiling ex7.cc  ====================
g++ -o ex7 -g ex7.cc
ex7.cc: In function void def_this ():
ex7.cc:15: request for `this' not in a class, struct, or union
====================  OUTPUT from compiling ex7.cc  ====================

Perhaps the error message:

	"Illegal attempt to use 'this' in a non-member function"

would be more correct, or am I missing something?
This error was produced on a SUN 3/280 (running SUN OS 3.5)
using g++ (1.36.1).

==============================  File: ex7.cc  ==============================
#include <stream.h>
class T{
    char s[500];
    friend void def_this();
 public:
    T() {
	def_this(); cout << "The value of 'this' is " << (int)this << "\n";
    };
    ~T() {
	cout << "In ~T, the value of 'this' is " << (int)this << "\n";
	this = 0;
    }
};

void def_this() { this = (T *) 0x43; }

main(int argc, char* argv[])
{
    T a1;
}
==============================  File: ex7.cc  ==============================


patrick (Patrick Steranka @ Corporation for Open Systems)
	-- patrick@cos.com
	-- patrick%cos.com@uunet.uu.net
	-- {uunet, sundc, decuac, hqda-ai, hadron}!cos!patrick

P.S.	If this kind of a report is too "nit-picky", then tell
	me to stop sending them and I will.