Re: [Boost-users] Testing whether result_of<F(U)> is a valid expression

Subject: Re: [Boost-users] Testing whether result_of<F(U)> is a valid expression
From: oswin krause (oswin.krause_at_[hidden])
Date: 2013-02-08 14:33:22

Hi,

thanks for both answers! Jeffreys suggestion is just perfect and so 
extremely nice, that i just have to link it :)

http://www.boost.org/doc/libs/1_52_0/doc/html/proto/appendices.html#boost_proto.appendices.implementation.function_arity

awesome stuff!

Also thanks Mathias. Your trick using F::result< F(Block<T>) >::type 
instead of boost::result_of is a nice way to solve the problem pre 
C++11, however it would not generalize to C++11 compilers where I would 
not be able to require the existence of the struct. As I want to support 
both, this is unfortunately ruled out. But many thanks!

Greetings,
Oswin

First of all, I can't use C++11, so i am bit a in a disadvantage.

On 08.02.2013 18:26, Mathias Gaunard wrote:
>
>
> Both can be done using SFINAE, the latter will require a recent enough 
> compiler that supports generalized SFINAE (GCC does it since 4.6 I 
> believe).
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