Open Radar

 
Summary:
When you == two ImplicitlyUnwrappedOptionals, Swift unwraps them and uses their type’s equality operator. It should instead treat them like regular Optional types, comparing them in a nil-safe way.

Steps to Reproduce:
1. Write code like this in a Playground:

    let x: Int! = 1, y: Int! = nil
    x == y

Expected Results:
“false” in the timeline.

Actual Results:
EXC_BAD_INSTRUCTION because Swift tried to unwrap x and y to pass them to ==(Int, Int) -> Bool.

Notes:
While this isn’t *wrong* per se, it can be a nasty surprise. Providing something like the existing ==<T: Equatable>(Optional<T>, Optional<T>) -> Bool overload for IUOs, on the other hand, would yield safer behavior without changing any code that doesn’t currently crash.