Re: [boost] is_nan

From: John Maddock (john_at_[hidden])
Date: 2006-07-25 08:34:19

Johan Råde wrote:
> I agree that having the three functions
>
>      is_infinite (or maybe is_infinity)
>      is_plus_infinity
>      is negative_infinity
>
> is a good idea.
>
> John's proposal has the function is_infinity, in the sense of both
> plus
> and minus infinity, but not the functions is_plus_infinity and
> is_negative_infinity.
>
> Maybe John's intention is that one should test for plus infinity by
>      writing is_infinity(x) && x >= 0
> That would work, but is probably inefficient.

For is_plus_infinity why not just:

x > std::numeric_limits<T>::max()

?

John.