isInfinite isInadequate

[deadalnix]

On Tuesday, 12 March 2013 at 15:02:44 UTC, monarch_dodra wrote:
> Right, that's what I said. This first paragraph was just about 
> enum empty = false.
>
> The actual "isInfinite" discussion comes later.
>
> Another point: isInfinite is useful, if only to propagate 
> infiniteness. For example: "1.repeat().map"a * 2"()". If "map" 
> didn't know that repeat is infinite, it would simply provide 
> the "dumb" empty implementation, and the final range will have 
> lost it's infinite trait.

That will always be optimized away without trouble by existing 
compilers. You'd loose the character of infinitness, but it seems 
to me like a lot of trouble as it add a whole class of things to 
consider when implementing wrapper ranges, for benefice that you 
can already get most of the time.

Note that something like computeIfCTFEable!(r.empty, true) would 
be much more beneficial than the actual implementation.