use std::fmt::Debug;

mod b {
    pub fn fun_b() {}
}

mod a
{
    use std::fmt::Debug;
    use b::fun_b;

    trait A : Debug {}

    fn fun_a() {
        fun_b();
    }

    mod c
    {
        /* NOTE: SHOULD be here - dependency not transistive, not implicit */
        use b::fun_b;
        /* dependency should be declared explicitly, no "embedded" semantics */
        use a::fun_a;

        pub fn fun_c() {
            fun_b();
            fun_a();
        }
    }
    /* mod in enclosing scope is also use for it */
    fn fun_g() {
        c::fun_c();
    }
}

fn main() {

}