Nested Functions

And in case you haven’t had enough of functions from this chapter, it’s always good to know that in Swift, you can have a function inside a function:

 func myFunctionWithNumber(someNumber: Int) {
 
  func increment(var someNumber: Int) -> Int {
  return someNumber + 10
  }
 
  let incrementedNumber = increment(someNumber)
  println("The incremented number is \(incrementedNumber)")
 }
 
 myFunctionWithNumber(5)
 // The incremented number is 15
 @end

Swift functions have a lot of options and a lot of power. As you start writing in Swift, remember: with great power comes great responsibility. Optimize for readability over cleverness!

Swift best practices haven’t been fully established yet, and the language is still constantly ...

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