Variadic Mixin/Template classes?

[vit]

On Saturday, 25 November 2017 at 09:52:01 UTC, Chirs Forest wrote:
> I'd like to make a class that takes multiple template types (1 
> - several) which can hold an array/tuple of a second class that 
> are instantiated with those types.
>
> class Bar(T) {
>     T bar;
> }
>
> class Foo(T[]){ // not sure how to take variadic types here?
>     Bar!(?)[] bars; //not sure how I'd define an array/tuple of 
> multiple types
>
>     this(){
>         foreach(int i, b; bars) b = new Bar!T[i];
>     }
> }
>
> void main(){
>     auto foo = new Foo!(string, int, string, ubyte[2]);
>
>     foo.bars[0].bar = "hello";
>     foo.bars[1].bar = 23;
>     foo.bars[2].bar = "hello";
>     foo.bars[3].bar[0] = 88;
>     foo.bars[3].bar[1] = 99;
>
>     auto foo2 = new Foo!(ubyte, string);
>     foo.bars[0].bar = 9;
>     foo.bars[1].bar = "world";
> }

import std.meta : staticMap;

class Bar(T) {
     T bar;
}

class Foo(Ts...){
     staticMap!(Bar, Ts) bars;

     this(){
	static foreach(i, alias T; Ts) bars[i] = new Bar!T;
     }


}

void main(){
     auto foo = new Foo!(string, int, string, ubyte[2]);

     foo.bars[0].bar = "hello";
     foo.bars[1].bar = 23;
     foo.bars[2].bar = "hello";
     foo.bars[3].bar[0] = 88;
     foo.bars[3].bar[1] = 99;

     auto foo2 = new Foo!(ubyte, string);
     foo2.bars[0].bar = 9;
     foo2.bars[1].bar = "world";
}