The Swift Programming Language--

Basic Operators

• Assignment Operator
  let (x, y) = (1, 2)

• Arithmetic Operators
  let str = "Hello" + "World" // '+' operator

Remainder Operator. The sign of b is ignored for negative values of b. This means that a%b and a%-b always give the same answer.

  let remains = 8%2.5 // 0.5

++ and -- can be used for any integer and floating-point type.

  let minusSix = -6
  let alsoSix = +minusSix // -6, '+' does not do anything

• Nil Coalescing Operator
  a ?? b // a is optional, b is the actual type of a
  a != nil ? a! : b

  let str: String = "Hello"
  var str1: String?// default set to nil
  
  var str2 = str1 ?? str // Hello, since str1 is nil
  

• Range Operator
  for i in 1...5 {
  print(i)
  }//1 2 3 4 5

  for i in 1..<5 {
     print(i)
  }// 1 2 3 4