Type functions example printing class hierarchy

[Stefan Koch]

On Friday, 21 August 2020 at 16:19:36 UTC, Stefan Koch wrote:

> class_hierarchy(A):
> A -> Object
>
> class_hierarchy(B):
> B -> A
> A -> Object
>
> class_hierarchy(C):
> C -> A
> A -> Object
>

Also I would have liked to write a template which produces the 
same output;
So I could show it as a comparison.
But I could not get it to work, (which is one data-point)
So If anyone how is more adapt at using recursive templates than 
me could provide an implementation, that'd be nice.