interface Eq {
    eq(other Eq) bool
}

interface Ord {
    Eq
    lt(other Ord) bool
}

// implement Ord for Int
struct Int {
    value int
}

fn (i Int) eq(other Ord) bool {
    if other is Int {
        return i.value == other.value
    }
    return false
}

fn (i Int) lt(other Ord) bool {
    if other is Int {
        return i.value < other.value
    }
    return false
}

fn compare(x Ord, y Ord) {
    println(x.eq(y))
    assert !x.eq(y)
    println(x.lt(y))
    assert x.lt(y)
}

fn test_interface_embedding_with_interface_para() {
    compare(Int{1}, Int{2})
}