[boost] Re: move semantics

From: Fredrik Blomqvist (fredrik_blomqvist_at_[hidden])
Date: 2004-04-19 08:15:05

David Abrahams wrote:
> Andrea Torsello <torsello_at_[hidden]> writes:
>
[snip]
>> Yes, actually different compilers seem to act differently here.
>> Since the compiler is free to copy const rvalues to non-const
>> rvalues and optimize the copy away, I would consider returning a
>> const temporary an odd thing to do. I am curious: does anyone have a
>> use-case for it?
>
> I doubt it; it doesn't seem like a very important case.  It could be
> used to have some effects on overload resolution I suppose, but it's
> hard to imagine that being useful in real code.
>
Just a comment on the 'const temporary return' issue.
I'd say it's not really an issue of whether it's useful per se, but how it
is _actually used_ in real code as a "safety" feature.
I.e to prevent: (a*b) = c;
Scott Meyers' Effective C++, item 21, labels this "The Right Thing To Do".
I've seen similar recommendations in a couple of coding-guidelines and
several times in real code, most likely inspired by EC++ or similar.
Thus it will appear in real code if nothing else for a matter of style.

// Fredrik Blomqvist