What goes into the body of the function?

Question

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

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

Answer 1 · 2015-07-07T05:21:03Z

July 7, 2015 5:21am

First of all you need to restructure your function to 1) take in not just one parameter of type function, but also the two integers that the function should evaluate, and 2) return an integer. I have used x an y to point out that the arguments passed in has absolutely nothing to do with the arguments in differenceBetweenNumbers - except for what you do with them inside the function mathOperation. The argument operation can be any other function that takes two integers as parameters and returns an integer - like differenceBetweenNumbers.

func mathOperation(operation: (Int,Int) -> Int, x: Int, y: Int) -> Int {
    //do something with the arguments and return an integer
}

I will try to let you figure out for yourself "what goes into the body of the function" and how to call it. But if you can't make it work, ask again and I will elaborate...

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Khambrel Davis

Khambrel Davis

What goes into the body of the function?

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Rasmus Rønholt

Rasmus Rønholt