constraint on variadic template

[Gary Willoughby via Digitalmars-d-learn]

On Wednesday, 7 December 2016 at 16:35:52 UTC, Alex wrote:
> mixin template S(T...)
> {
>     void run()
>     {
>         foreach(s; T)
>         {
>             static assert(__traits(hasMember, s, "run"));
>         }
>     }
> }
>
> How to formulate the check inside the foreach as a template 
> constraint with
> mixin template S(T...) if(???)

Will some like this work?

     import std.range.primitives;

     mixin template S(T...) if(__traits(hasMember, 
ElementType!(T), "run"))
     {
         ...
     }

https://dlang.org/phobos/std_range_primitives.html#ElementType