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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Connor Zwick
Connor Zwick
9,557 Points
Posted by Connor Zwick
Connor Zwick
9,557 Points

Treehouse Not Accepting My Code!

I have tried this code in a Swift playground and it works perfectly fine, but when I try to submit it to Treehouse, it says that I'm not utilizing all of the functions! Is there something wrong with my code?

higherOrderFunctions.swift 
/** 
  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
}

// Enter your code below

func mathOperation(mathOp : (Int, Int) -> (Int), number1 : Int, number2 : Int) -> Int {
    return mathOp(number1, number2)
}

let difference = mathOperation(differenceBetweenNumbers, 10, 5)