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Re: Should we have a core language operator for forwarding arguments?

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On 2011-11-10 02:10, Nikolay Ivchenkov wrote:
>
>   Consider the following example:
>
>       template<class T>
>           void f(T&&t)
>       {
>           g(std::forward<T>(t));
>       }
>
>   We can notice that parameter t contains sufficient information for
>   "perfect forwarding":
>
>       #define FWD(x) static_cast<decltype(x)>(x)
>
>       template<class T>
>           void f(T&&t)
>       {
>           g(FWD(t));
>       }
>
>   This code might be even simpler if we had unary operator&&    with the
>   similar semantics:
>
>       &&reference returns static_cast<decltype(reference)>(reference)
>
>   Example:
>
>       template<class T>
>           void f(T&&t)
>       {
>           g(&&t);
>       }
>
>   I think that simple things should be expressed by simple constructs.
>   std::forward should be used where its function argument would not
>   contain sufficient information, otherwise we supply redundant
>   information and have too lengthy code (especially when std::forward is
>   included in a single expression several times).

I agree, I find your example very much compelling. There are some cases,
where I still prefer using std::forward, namely where I could
(unintentionally) have tried to convert an rvalue to an lvalue as
analysed in

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2009/n2951.html

This does not happen in your examples, though.

Thanks&   Greetings from Bremen,

Daniel Krügler


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Should we have a core language operator for forwarding arguments? Nikolay Ivchenkov <tsoae@mail.ru> - 2011-11-09 19:10 -0600
  Re: Should we have a core language operator for forwarding arguments? Daniel Krügler<daniel.kruegler@googlemail.com> - 2011-11-10 07:58 -0800
  Re: Should we have a core language operator for forwarding arguments? Arne Mertz<arnemertz@googlemail.com> - 2011-11-10 10:41 -0800
    Re: Should we have a core language operator for forwarding arguments? Nikolay Ivchenkov<tsoae@mail.ru> - 2011-11-11 13:04 -0800
      Re: Should we have a core language operator for forwarding arguments? Miles Bader <miles@gnu.org> - 2011-11-12 11:33 -0800
        Re: Should we have a core language operator for forwarding arguments? Nikolay Ivchenkov<tsoae@mail.ru> - 2011-11-12 21:46 -0800

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