First life-signs of type functions

[Nick Treleaven]

On Saturday, 9 May 2020 at 06:39:20 UTC, Stefan Koch wrote:
>     alias p;
>     p = t;
>     bool good = is(typeof(__traits(parent, p)));
>     while(good)
>     {
>         p = __traits(parent, p);
>         result = p.stringof ~ "." ~ result;
> //        result = __traits(identifier, parent) ~ "." ~ result;
>         good = is(typeof(__traits(parent, p)));
>     }

Very cool!

When `alias[]` is implemented, would this work:

bool anySatisfy(alias Tem, alias[] S)
{
     bool found;
     alias E;
     while (S.length)
     {
         E = S[0];
         if (Tem!E)
             return true;
         S = S[1..$];
     }
     return false;
}

enum isPointer(T) = is(T : E*, E);
pragma(msg, anySatisfy!(isPointer, int, char, void, int*, byte));

Any idea how fast this would be compared to `core.internal.traits 
: anySatisfy` (which doesn't use template recursion)?