Re: [boost] [safe_numerics] review

Subject: Re: [boost] [safe_numerics] review
From: Peter Dimov (lists_at_[hidden])
Date: 2017-03-12 13:18:54

> In fact, the promotion policy can be eliminated entirely if the underlying 
> type is always made automatic.

Specifically, instead of the current arrangement where all user-visible 
templates resolve to safe_base<T, Min, Max, PP, EP>, and assuming for a 
moment that we only support the range of intmax_t, we could have

    template<intmax_t Min, intmax_t Max, class EP> class safe_range;

as a basis and then define safe<T, EP> as safe_range<min(T), max(T), EP>.

Unfortunately, due to the need to support uintmax_t, which doesn't fit in 
intmax_t, we'd need two safe_range types and support for mixed operations, 
which would complicate things a bit on the implementation side.

On the user side though there'd be no need for promotion policies.

Although operator~ would no longer be supportable. One would have to 
explicitly xor with ~0 (of the correct type.)