func foo(idxOpt: Int?) {
  if let idx = idxOpt {
    print(idx)
  }
}

func bar(fooOpt: Int?) {
  guard let foo = fooOpt else {
return
}
let incrementedFoo = foo + 1
    print(incrementedFoo)
}

func fooBar(fooOpt: Int?) {
  if let foo = fooOpt {
    let incrementedFoo = foo + 1
    print(incrementedFoo)
    print(foo)
  }
}

func barFoo(idxOpt: Int?) {
  if let idx = idxOpt {
    print(idx)
  } else {
    print("nil")
  }
}