🚀 go-pugleaf

kanze <kanze@lts.sel.alcatel.de> writes:

>In article <45sl3a$coc@engnews2.Eng.Sun.COM> clamage@Eng.sun.com
>(Steve Clamage) writes:

>|> damian@molly.cs.monash.edu.au (Damian Conway) writes:

>|> >Then is it possible to set up a class X wherein:

>|> >	X x(1);
>|> >and
>|> >	X x = 1;

>|> >behave differently?

>|> Yes.  Silly example: Write a message to the terminal from the copy
>|> constructor. If the copy is optimized away, you won't see the message.

>I don't think that is what he was looking for.  As far as I know,
>there is no way of *ensuring* that the above will both be legal, but
>have garanteed different run-time semantics.

Yes, that was what I was asking.

>It is trival to make the first legal, and the second illegal, which, I
>suppose is a way of making them behave differently at compile time.

:-)

BTW: What was the rationale for making something as fundamental as copy
     initialization non-portable (in the sense that it has no guaranteed
     semantics)?


damian

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       Clayton 3168                  quote: "A pessimist is never disappointed.
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