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Re: Is removing necessity of std::move for local variables used for the last time a good proposal?

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> > [...]
>
> > So, do you think is it a good idea to add a rule to C++ language that:
>
> >
>
> > If the automatic variable is used as a source for copying and this is
>
> > the last time variable is used - then move is used instead of copy.
>
> >
>
> > If the above rule would be added to language - then to my best
>
> > understanding - there would be no need to use std::move in my example.
>
> > [...]
>
>
>
> So far, as you probably know, a compiler is not required nor allowed
>
> to do that. I think there is some value in further analyzing the
>
> impact of such a rule. We would not want this rule to break something.
>
> I've trouble coming up with examples that would break, but it does
>
> not mean that there are none. It would be nice to have a somewhat
>
> formal proof under reasonable assumptions that nothing could go wrong.
>
>
>

Hello,

sg - thanks for quick response.

Well, I just followed this guidance:
"The public can submit proposed defect reports via the Internet news
group comp.std.c++ "
from C++ standard webpage
(http://www.open-std.org/jtc1/sc22/wg21/docs/standards#14882).

And I have no idea how to find a "formal proof [...] that nothing
could go wrong".

I hope this is everything from my side to raise this issue to C++
standard folks - but if I am wrong - please tell me.

And a general comment: C++11 is great, many things can be written in
more readable, more compact and, what I appreciate a most, shorter
way.
But this one feature, with this "annoying" std::move() needed almost
everywhere - is one thing that really s...

BR,
Piotr


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Is removing necessity of std::move for local variables used for the  last time a good proposal? Piotr Nycz <piotrwn1@googlemail.com> - 2014-05-30 15:32 -0600
  Re: Is removing necessity of std::move for local variables used for  the  last time a good proposal? SG <s.gesemann@googlemail.com> - 2014-06-05 12:31 -0600
    Re: Is removing necessity of std::move for local variables used for  the  last time a good proposal? Kalle Olavi Niemitalo <kon@iki.fi> - 2014-06-07 01:25 -0600
    Re: Is removing necessity of std::move for local variables used for   the  last time a good proposal? Piotr Nycz <piotrwn1@googlemail.com> - 2014-06-07 02:33 -0600
      Re: Is removing necessity of std::move for local variables used for   the  last time a good proposal? Daniel Krügler <daniel.kruegler@googlemail.com> - 2014-06-08 01:32 -0600
        Re: Is removing necessity of std::move for local variables used for    the  last time a good proposal? Piotr Nycz <piotrwn1@googlemail.com> - 2014-06-17 07:25 -0600

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