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From: ark@alice.UUCP (Andrew Koenig)
Newsgroups: comp.lang.c++
Subject: Re: address of virtual function (revisited)
Message-ID: <9263@alice.UUCP>
Date: 29 Apr 89 02:12:49 GMT
References: <904@garya.Solbourne.COM>
Organization: AT&T Bell Laboratories, Liberty Corner NJ
Lines: 25

In article <904@garya.Solbourne.COM>, garya@Solbourne.COM (Gary Aitken) writes:

> Or am I missing something here?  If I do
> 	fp = &A::f;
> and subsequently do a
> 	(bp->*fp)();
> will this somehow go through the virtual table and actually call B::f if
> bp is REALLY a B* object pointer?


Yes.


What you can't do is bind an object and a function pointer into
a single value.  That is, there's no type you can give x
that will let you do this sanely:

	x = &bp->f;

It would be nice, but it is extremely difficult to compile into
C because C doesn't let you get your tentacles into its
calling sequence portably.
-- 
				--Andrew Koenig
				  ark@europa.att.com