C++ std::map equivalent? (An in-order iterable associative container)

[bearophile via Digitalmars-d-learn]

Mark Isaacson:

> Got it, no native support. Most unfortunate.

What native support are you talking about?


> I've always been vehemently against losing self-documentation 
> via the std::pair/tuple based solution to the problem.

What self documentation are you losing in D?


> I ended up rolling my own solution that lets you give 
> meaningful names to the wrapper struct's data members: 
> http://pastebin.com/cKLccqFn

What's bad about this?

void main() {
     import std.stdio, std.container, std.typecons;

     alias Two = Tuple!(string,"str", int, "bob");
     alias MyTree = RedBlackTree!(Two, q{a.str < b.str}, false);

     auto map = new MyTree(Two("hello", 5), Two("zbd", 3), 
Two("abc", 9));

     map[].writeln;
     auto rng = map[];
     assert(rng.front == map.Elem("abc", 9));
     assert(rng.front.str == "abc");
     assert(rng.front.bob == 9);
}


Bye,
bearophile