trait Trait<T> {}
trait Proj<'a> {
    type Assoc;
}
fn foo<T>()
where 
    T: for<'a> Proj<'a, Assoc = for<'b> fn(<T as Proj<'b>>::Assoc)>,
    (): Trait<<T as Proj<'static>>::Assoc>
{
}