Compile-Time Interfaces (Concepts)

[Nordlöw]

AFAIK there is no compile-time variant of interfaces right?
Why is that?

Wouldn't it be nice to say something like

    struct SomeRange realize InputRange
    {
        /* implement members of InputRange */
    }

and then the compiler will statically check that that all members 
are implemented correctly.

I guess this requires some new syntax to describe what an 
InputRange is.

Kind of like C++ Concepts.