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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Justin Bane
Justin Bane
7,850 Points

Just not getting this test - It seems to fail regardless of what I do

My code (hopefully shown below) works exactly a it should in a playground. Why does it continue to fail in the test? I have checked the spelling and the function of the code - any help?

  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, a: Int, b: Int) -> (Int) {
  return mathOp(a, b)

let difference = mathOperation(differenceBetweenNumbers, 3, 1)