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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Kamran Ismayilov
Kamran Ismayilov
5,753 Points
Posted by Kamran Ismayilov
Kamran Ismayilov
5,753 Points

Higer ordered Function Challenge

Why my code is wrong?

/** 
  For this code challenge, let’s define a math operation as a function that 
  carries out some work on two integers and returns an integer as well. An 
  example is the function below, `differenceBetweenNumbers`, which takes two 
  integers and calculates the difference between the numbers. After calculating, 
  it returns the difference.
**/

func differenceBetweenNumbers(a: Int, b:Int) -> (Int) {
  return a - b
}

func mathOperation() -> (Int, Int) -> Int {
   func differenceBetweenNumbers(a: Int, b: Int) -> (Int) {
      return a - b
   }
   return differenceBetweenNumbers
}

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Hello:

I gave an explanation to another student that maybe you want to look into, it may help you understand this a bit better. You can click here to read all about it.