transpose.d

import std.meta, std.typetuple, std.traits;
template ArrayTypeOf(int n, T...) {
	static if (T.length == 0)
		alias ArrayTypeOf = T;
	else
		alias ArrayTypeOf = AliasSeq!(T[0][n], ArrayTypeOf!(n, T[1..$]));
}

struct Transpose(T, int n) {
	alias names = FieldNameTuple!T;
	struct Accessor {
		int index;
		Transpose!(T, n) *ptr;
		ref auto opDispatch(string name)() {
			enum x = staticIndexOf!(name, names);
			return ptr.store[x][index];
		}
	}
	ArrayTypeOf!(n, Fields!T) store;
	auto opIndex(int i){
		return Accessor(i, &this);
	}
}
struct A{
	int a;
	float b;
}
void main() {
	Transpose!(A, 10) xx;
	import std.stdio;
	writeln(xx[2].a);
}