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Re: Request for std::vector and possibly others: mi

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henrik.vallgren@stream-space.com (henrikv) wrote (abridged):
> IMO, telling the vector which constructor to use isn't "improper
> use".

That's what emplace_back does. It seems to me to be exactly what you
want, except
it adds a single item instead of a range of them. Thus your:

   dummies.resize(1000, g_no_init);

would be written:
   dummies.reserve(1000);
   for (int i = 0; i < 1000; ++i)
       dummies.emplace_back(g_no_init);

Either way you'd be relying on the optimiser.


> I'm thinking *parallel* loop here, so neither order, nor race
> conditions can be predicted.

Your resize would need to be done before the parallel code kicked off,
and so would
the above loop. Emplace_back() is not used by the parallel code.

That said, replacing:
   resize( size_type count, const value_type &value );

with:
   template<class... Args>
   void resize( size_type count, Args&&... args );

does seem like a reasonable request to me. It would be useful whenever
constructing
a new value_type with args was preferable to copying a value_type that had been
constructed with args. I don't see a drawback, other than the issues that arise
whenever the standard is changed.

-- Dave Harris, Nottingham, UK.


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Thread

Request för std::vector and possibly others: minimal initalization henrikv <henrik.vallgren@stream-space.com> - 2012-03-19 23:35 -0700
  Re: Request för std::vector and possibly others: minimal initalization Francis Glassborow<francis.glassborow@btinternet.com> - 2012-03-21 11:35 -0700
    Re: Request för std::vector and possibly others: minimal initalization henrikv<henrik.vallgren@stream-space.com> - 2012-03-23 17:09 -0700
      Re: Request för std::vector and possibly others: minimal initalization Daniel Krügler <daniel.kruegler@googlemail.com> - 2012-03-24 19:25 -0700
      Re: Request för std::vector and possibly others: minimal initalization Francis Glassborow <francis.glassborow@btinternet.com> - 2012-03-24 19:28 -0700
  Re: Request för std::vector and possibly others: minimal initalization Jason McKesson<jmckesson@gmail.com> - 2012-03-21 11:35 -0700
    Re: Request för std::vector and possibly others: minimal initalization henrikv<henrik.vallgren@stream-space.com> - 2012-03-23 17:10 -0700
      Re: Request för std::vector and possibly others: minimal initalization Jason McKesson<jmckesson@gmail.com> - 2012-03-24 17:55 -0700
      Re: Request for std::vector and possibly others: mi brangdon@cix.compulink.co.uk (Dave Harris) - 2012-03-24 19:24 -0700
      Re: Re: Request för std::vector and possibly others: minimal initalization jgk@panix.com (Joe keane) - 2012-03-27 12:10 -0700
    Re: Request för std::vector and possibly others: minimal initalization Kevin McCarty<kmccarty@gmail.com> - 2012-03-23 17:11 -0700
      Re: Request för std::vector and possibly others:   minimal initalization Miles Bader<miles@gnu.org> - 2012-03-24 17:55 -0700
        Re: Request för std::vector and possibly others: minimal initalization henrikv <henrik.vallgren@stream-space.com> - 2012-03-25 23:14 -0700
      Re: Request för std::vector and possibly others: minimal initalization Jason McKesson <jmckesson@gmail.com> - 2012-03-24 19:27 -0700
      Re: Request för std::vector and possibly others: minimal initalization Pedro Lamarão<pedro.lamarao@gmail.com> - 2012-03-29 12:28 -0700
        Re: Request för std::vector and possibly others: minimal initalization Daniel Krügler <daniel.kruegler@googlemail.com> - 2012-03-29 13:17 -0700

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