Open Radar

 
Some languages, including GNU C, support a shorthand version of the ternary operator (?:) where the second operand is optional. This implicitly uses the first operand as the second operand also. It is often used when a check is required before returning a value, returning a default value instead when the check fails.

In Swift, optional chaining is one use case where this seems especially useful. For example, currently you need to repeat the chain in the second operand and remember to unwrap the resulting value:

override func intrinsicContentSize() -> CGSize {
  return user.image ? user.image!.size : CGSize(width: 100, height: 100)
}

Supporting a shorthand ternary operator would simplify this code:

override func intrinsicContentSize() -> CGSize {
  return user.image?.size ?: CGSize(width: 100, height: 100)
}

It might also be more efficient, as the chain only needs to be traversed once, making it functionally similar to:

override func intrinsicContentSize() -> CGSize {
  if let size = user.image?.size {
    return size
  } else {
    return CGSize(width: 100, height: 100)
  }
 }