Implement call?

[Aurel300]

E.g.:

if let x: Int = (call? ext.foobar()) as! Int {
  // ...
}

Possible issue – as? is also used with if let in Swift, so the above might be confusing if let x: Int = (call? ext.foobar()) as? Int { ... – is the else branch taken when the calls fails or when the type cast fails?

[nvgrw]

If we have Swift semantics with optionals this'd give you an error because you're trying to cast an optional type to a non-optional, optionally.

If foobar returns an int256, say, then after call you would expect to have an int256?. However Int is not an optional type, so even a forced cast would crash the compiler. There's no way for this to work. If you do as! Int? then obviously you would expect x to be of type Int?, which resolves the ambiguity here.