Sorting

sorting.swift

import Foundation

struct Message {
  var timestamp: Double
}

extension Message: Printable {
  var description: String {
    return "Message with timestamp \(self.timestamp)"
  }
}

var someMessages = [Message(timestamp: 30), Message(timestamp: 20)]

someMessages.sort({ $0.timestamp < $1.timestamp }) // is the same as...
print(someMessages) /* "[Message with timestamp 20.0, Message with timestamp 30.0]" */

someMessages.sort({ (message1: Message, message2: Message) -> Bool in
return message1.timestamp < message2.timestamp }) // this one. :-)

print(someMessages) /* "[Message with timestamp 20.0, Message with timestamp 30.0]" */