Purity, @safety, etc., in generic code

[deadalnix]

On Saturday, 23 February 2013 at 15:16:15 UTC, Steven 
Schveighoffer wrote:
> This actually is impossible to do with inout, unless your 
> ranges are pointers or arrays (believe me, I tried with 
> dcollections).  But that is not inout's fault, it's because we 
> have no way to specify tail-const arbitrary types.
>

I have read what come after, but clearly shouldn't have. This is 
the interesting thing to discuss. Can you expand on that ? Some 
code sample ?