trait Trait { const ASSOC: i32; } impl Trait for () { const ASSOC: &dyn Fn(_) = 1i32; //~^ ERROR the placeholder `_` is not allowed within types on item signatures for associated constants //~| WARN `&` without an explicit lifetime name cannot be used here //~| WARN this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release! } fn main() {}