Re: [boost] [Review] Boost.Type Traits Extension by Frederic Bron

Subject: Re: [boost] [Review] Boost.Type Traits Extension by Frederic Bron
From: Edward Diener (eldiener_at_[hidden])
Date: 2011-03-16 15:42:28

On 3/16/2011 2:49 PM, Jeffrey Lee Hellrung, Jr. wrote:
> On 3/14/2011 12:48 AM, Joel Falcou wrote:
>> Dear All,
>>
>> This is the first day of the fast track review of Frédéric Bron's
>> extensions to the Type Traits Library.This reviews will last until March
>> 18th, 2011 under my management. All comments and reviews are
>> very welcome.
> What is the community's feeling about adding a 3rd template parameter
> (or some other equivalent interface) to constrain the result type of the
> operator other than "is convertible to"? E.g., I've proposed adding the
> ability to pass a Boost.MPL metafunction to evaluate on the result type
> of the operation. One could use some other mechanism if one doesn't wish
> to couple Boost.TypeTraits to Boost.MPL. I'm motivated by the fact that,
> although checking convertibility seems like the most common use case
> (and the current interface is what I'd expect it to look like), one may
> want to constrain the result type further. For example, checking for an
> exact type match, or checking for rvalueness/lvalueness.
>
> I'd be willing to help add this capability, but if there is little or no
> support for it, then it needn't be further pursued.

I think you are overdoing and overcomplicating what is necessary.