What's wrong with my usage of std.algorithm.map in this code example?

[ag0aep6g via Digitalmars-d-learn]

On 05/25/2016 04:39 PM, Chris wrote:
> I see. Maybe it would be worth adding a wrapper to typecons.Tuple or
> std.range that helps to rangify tuples.

std.range.only is that wrapper.

> I cannot think of any use case
> right now. I never needed this and in the example that started this
> thread, it would keep the function from converting mixed tuples (cf. my
> example above).

I'm not sure what you're saying here. Should the wrapper support tuples 
with different element types? Can't be a range then as a range has just 
one element type.