Re: [boost] function convert() -- do you find it useful?

Subject: Re: [boost] function convert() -- do you find it useful?
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2014-06-29 05:13:31

On Sunday 29 June 2014 10:15:00 Vicente J. Botet Escriba wrote:
> Le 28/06/14 23:34, Andrey Semashev a écrit :
> > On Sun, Jun 29, 2014 at 12:58 AM, Andrzej Krzemienski
> > 
> > <akrzemi1_at_[hidden]> wrote:
> >> Hi,
> >> This is the second time that I have found the following function useful
> >> when playing with variants of  Optional library:
> >> 
> >> template <typename T, typename U>
> >> typename std::enable_if<std::is_convertible<U, T>::value, T>::type
> >> convert(U && u)
> >> { return std::forward<U>(u); }
> >> 
> >> It performs an implicit conversion from U to T, but you can call it
> >> explicitly.
> > 
> > Isn't it what implicit_cast does? See boost/implicit_cast.hpp.
> 
> Andrey, is implicit_cast SFINAE friendly?

I'm not sure, but I think so. It doesn't seem callable if U is not 
convertible.