struct Tuple2[A, B] {
    a A
    b B
}

// map to array of Tuple2[int, Tuple2[key, value]] tuples
fn map_to_array_int_kv[K, V](m map[K]V) []Tuple2[int, Tuple2[K, V]] {
    mut r := []Tuple2[int, Tuple2[K, V]]{cap: m.len}
    mut i := 0
    for k, v in m {
        r << Tuple2[int, Tuple2[K, V]]{i, Tuple2[K, V]{k, v}}
        i += 1
    }
    return r
}

// map to array of Tuple2[int, Tuple2[Tuple2[key, value], Tuple2[value, key]]] tuples
fn map_to_array_int_kv_vk[K, V](m map[K]V) []Tuple2[int, Tuple2[Tuple2[K, V], Tuple2[V, K]]] {
    mut r := []Tuple2[int, Tuple2[Tuple2[K, V], Tuple2[V, K]]]{cap: m.len}
    mut i := 0
    for k, v in m {
        r << Tuple2[int, Tuple2[Tuple2[K, V], Tuple2[V, K]]]{i, Tuple2[Tuple2[K, V], Tuple2[V, K]]{Tuple2[K, V]{k, v}, Tuple2[V, K]{v, k}}}
        i += 1
    }
    return r
}

fn main() {
    x := {
        'one': 1
        'two': 2
    }
    y := {
        3: 'three'
        4: 'four'
    }

    println(x)
    rx1 := map_to_array_int_kv(x)
    println(rx1)
    rx2 := map_to_array_int_kv_vk(x)
    println(rx2)

    println(y)
    ry1 := map_to_array_int_kv(y)
    println(ry1)
    ry2 := map_to_array_int_kv_vk(y)
    println(ry2)

    // test typeof(X).name
    zx1 := []Tuple2[int, Tuple2[string, int]]{}
    println(typeof(zx1).name)
    zx2 := []Tuple2[int, Tuple2[Tuple2[string, int], Tuple2[int, string]]]{}
    println(typeof(zx2).name)
}