Ranges longer than size_t.max

[Peter Alexander]

On Saturday, 29 December 2012 at 01:56:04 UTC, Simen Kjaeraas 
wrote:
>   @property auto length()
>   {
>       CommonType!(staticMap!(LengthType, R)) result = 0;
>       foreach (i, Unused; R)
>       {
>           result += source[i].length;
>       }
>       return result;
>   }
>
> This would thus support BigInt .length just as well as size_t, 
> byte,
> or whatever.

This doesn't solve the issue. For example, even with your update, 
the code snippet I provided in the original post with iota and 
chain would still break (assuming iota(size_t.max).length returns 
a size_t).

Also, if we allow BigInt, even with better support in CommonType 
it would significantly complicate Phobos with LengthType!Range 
popping up everywhere.