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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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On Friday, May 30, 2014 10:40:05 PM UTC+2, Piotr Nycz wrote:
> [...]
> 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.
>
> My motivation is simple: there are plenty of C++03 where std::move was
> not used. So, according to C++11 rules we shall add almost everywhere
> this std::move?

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.

Cheers!
sg


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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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