Re: [boost] [MPL.Math] ratio

Subject: Re: [boost] [MPL.Math] ratio
From: Cromwell Enage (sponage_at_[hidden])
Date: 2008-11-14 04:17:58

--- On Fri, 11/14/08, Cromwell Enage wrote:
> Sections: 20.4.1 [Class template ratio], 20.4.2 [Arithmetic
> on ratio types]

Also 20.4.3 [Comparison of ratio types]

[snip rest of report]

> We should also require that each of the arithmetic
> metafunctions inherit from std::ratio if we want to allow
> the following usage (note the change from R::type::num to
> R::num).
> 
>     template <typename R>
>     struct absolute_ratio
>       : boost::mpl::eval_if<
>             R::num < 0
>           , boost::mpl::negate<R>
>           , R
>         >
>     {
>     };

For the sake of completeness, if the arithmetic metafunctions are to inherit from std::ratio, so should the comparison metafunctions.

Cheers,
Cromwell D. Enage