#![feature(existential_type)]
pub trait T {
    fn bla() -> ();
}

pub struct S {
  v: u64
}

impl T for S {
    fn bla() -> () {}
}

existential type TE: T;
pub fn bla() -> TE {
    return S {v:1}
}

pub fn bla2() -> TE {
    bla()
}