Protocols vs Concepts?

[Dicebot]

On Wednesday, 20 November 2013 at 23:35:02 UTC, Meta wrote:
> Something that's almost exactly what you're looking for:
>
> http://dlang.org/phobos/std_typecons.html#.wrap
> http://dlang.org/phobos/std_typecons.html#.unwrap

Wrong-wrong-wrong! `wrap` is different, though with some 
implementation similarities. First, it only works on polymorphic 
types. Second, it actually creates a wrapper type while point of 
typical `implements!(T, I)` is duck typing verification as-is in 
templated code. It is basically a more generic form of 
`isXXXRange`.