redBlackTree

auto rbt1 = redBlackTree(0, 1, 5, 7);
auto rbt2 = redBlackTree!string("hello", "world");
auto rbt3 = redBlackTree!true(0, 1, 5, 7, 5);
auto rbt4 = redBlackTree!"a > b"(0, 1, 5, 7);