using the full range of ubyte with iota

[Dominikus Dittes Scherkl via Digitalmars-d-learn]

On Sunday, 25 January 2015 at 10:42:51 UTC, bearophile wrote:
> Vlad Levenfeld:
>
>> What's this about !`[]` and std.range.uniform?? It's not in 
>> the documentation.
>
> It's an enhancement I have proposed.

Hm. I had more something in mind like "paramCast" - a kind of big 
scissors that cut everything a function is called with to the 
size it can cope with, so replacing

map!fn

not with

map!(x => fn(cast(ParameterTypeTuple!fn[0])x)

but instead with

map!(paramCast!fn)

Because this is useful in more situations, e.g. in every place 
where you know the values would fit into the parameter (and for a 
single call would use a cast).

But so far I couldn't manage to make this work :-/