Re: Temporaries

From:
Victor Bazarov <v.Abazarov@comAcast.net>
Newsgroups:
comp.lang.c++
Date:
Wed, 12 Aug 2009 12:37:16 -0400
Message-ID:
<h5ur37$qca$1@news.datemas.de>
Prasoon wrote:

Are all temporaries in C++ "rvalues"?


No.

According to me "yes".
Am I right?


What do you think?

However consider the following code.

#include <iostream>

int a;

int& foo()

{

return a;

}

int main()

{

foo()=6;

}

Is there any temporary created in the above code?


Not really. I wanted to say "yes, for the '6'", but since 'int' is not
a class, even semantically there is no copy-assignment operator that
*might* require creation of a temporary...

According to me "no" there isn't any.

foo() returns just a reference to "a" (and no temporary created).
Correct me if I am wrong.


You need to do that when the return value of 'foo' is a class which can
be initialised from an int. There will be a temporary created so a
reference can be bound to it when that reference is passed to the
copy-assignment operator.

V
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