CT Inheritence structures

[Enamex via Digitalmars-d-learn]

On Saturday, 20 August 2016 at 00:46:15 UTC, Engine Machine wrote:
> I am trying to get Timon Gehr's code working, with some 
> modifications:
>
> void main()
> {
>
> 	import std.traits;
>
> 	auto a = new Type!("Animal", "Dog", "Pug")();
> 	Type!("Animal", "Dog") b = a;	
> 	Type!("Animal") c = b;	
>
> 	a.s = 1;
> 	b.z = 2;
> 	c.y = 3;
> }
>

Also:

     alias T1 = TemplateOf!(typeof(a));
     alias T2 = TemplateOf!(typeof(c));
     pragma(msg, "\n", T1!"As", " -- ", T2!"As", "\n"); // T1!"As" 
-- T1!"As"

That's extremely weird. It looks like template instantiations 
carry as their printable name (and comparison identifier, because 
`is(templateAlias == templateAlias2)` doesn't work) the name they 
were first instantiated through.

So even doing:

     pragma(msg, T1!("Animal", "Dog"))

would print `PT!("Animal", "Dog")` given that it had been 
instantiated already through another Type with ("Animal", "Dog") 
in the beginning of its tuple.