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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Sasha Kiselev
Sasha Kiselev
2,382 Points
Posted by Sasha Kiselev
Sasha Kiselev
2,382 Points

Help with closures challnge

I have this code and it runs in xcode playground but not in the online editor

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(opperation:(Int,Int) -> (Int),aMain:Int,bMain:Int) -> Int
{
    return opperation(aMain,bMain)
}
var differenceFunc = differenceBetweenNumbers
let difference = mathOperation(differenceFunc,5,4)

1 Answer

Chris Stromberg
PLUS
Chris Stromberg
Courses Plus Student 13,389 Points
Chris Stromberg
Chris Stromberg
Courses Plus Student 13,389 Points

Drop this line, its valid code, but not required.

var differenceFunc = differenceBetweenNumbers

First part of challenge

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

Second part of challenge

let difference = mathOperation(differenceBetweenNumbers, 4, 1)