trait First {}
trait Second {
    type Wow: First;
}
trait Third {
    type Lol: Second;
}
trait Forth {
    type Hmm: Third;
}

fn kek<One, Two, Three, Four>(_: Four)
where
    Four: Forth<Hmm = Three>,
    Three: Third<Lol = Two>,
    Two: Second<Wow = One>,
    One: First,
    One: Send,
    Two: Send,
    Three: Send,
    Four: Send,
{

}