Last Updated: January 05, 2018

Add a Ruby-like "spaceship operator" to Swift

This provides a Ruby-like "spaceship operator" (<=>) for Swift. For more idiomatic Swift this uses an enum, however if you really want to, you can use the provided rawValue the same way you would in Ruby:

import Foundation

enum Compare: Int {
 case Right = -1, Equal, Left
}

infix operator <=> {}

func <=> <T: Comparable>(left: T, right: T) -> Compare {
 if left == right {
 return .Equal
 } else if left > right {
 return .Left
 } else {
 return .Right
 }
}

1 <=> 1 // .Equal
2.4 <=> 2.9 // .Right
"b" <=> "a" // .Left
(0 <=> 1).rawValue // -1

switch 0 <=> 1 {
case .Equal, .Left: print("That's odd")
default: print("All good")
}
// prints "All good"

#ruby

#swift