Re: C++ virtual function calls

joe@sanskrit.ho.att.com (Joe Orost) writes:


>I don't think it is legal to hoist the virtual function lookup
>out of the loop:


>for( ...) {
> p->virt_func();
>}


>because "p" is passed to virt_func as "this", and therefore the
>function could change the subtype of "p", causing a different
>function to be called next time around the loop!


Hmmmm... you mean by doing something like "~typeofp(); new(p) typeofp(22);"?
I'm not sure this would be legal -- an interesting question for
comp.std.c++, if the comp.compiler moderator would pretty please
crosspost this to there (crossposting on two mod groups at once
can really be -- ahem -- "interesting"!-).




Alex
--
DISCLAIMER: these are TOTALLY personal opinions and viewpoints, NOT connected
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