pub fn translate_alias<Id, T, U, F, I>( interner: &mut I, alias: &AliasData<Id, T>, translate: F ) -> AliasData<Id, U>where T: TypePtr<Id = Id>, U: TypePtr<Id = Id>, Id: Clone, T::SpannedId: Clone, F: FnMut(&mut I, &T) -> U, I: TypeContext<Id, U>,