use std;

mod ht {
    iface hash {
        fn hash() -> uint;
        fn tostr() -> str;  // putting this into the interface is just a hack
                            // to give us a way to print keys. This doesn't go
                            // here at all.
    }

    type t<K,V> = [(K, V)];  // doesn't matter, we don't use it

    fn create<K:hash,V>() -> @t<K,V> {
        @[]
    }

    fn put<K:hash,V>(ht: @t<K,V>, k: K, v: V) {
        io::println(#fmt("ht put: %s hash to %ud", k.tostr(), k.hash()));
    }
}

mod Module1 {
    impl of ht::hash for uint {
        fn hash() -> uint { ret self; }
        fn tostr() -> str { ret #fmt("%ud", self); }
    }
    fn foo() {
        let h = ht::create::<uint, str>();
        ht::put(h, 3u, "hi"); // 3u.hash() == 3u here
        Module2::bar(h);
    }
}

mod Module2 {
    impl of ht::hash for uint {
        fn hash() -> uint { ret self / 2; }
        fn tostr() -> str { ret #fmt("%ud", self); }
    }
    fn bar(h: @ht::t<uint, str>) {
        ht::put(h, 3u, "ho"); // 3u.hash() == 1u here
    }
}

fn main (_args: [str]) {
    Module1::foo();
}