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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Angel E
PLUS
Angel E
Courses Plus Student 2,581 Points

Hey is this using swift 1.x syntax? my code is running ok in a Xcode 7 playground (iOS)

func mathOperation(mathFunction: (Int, Int) -> Int, a: Int, b: Int){ mathFunction(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
Angel E
Angel E
Courses Plus Student 2,581 Points
func mathOperation(mathFunction: (Int, Int) -> Int, a: Int, b: Int){ mathFunction(a,b) }

1 Answer

Angel E
PLUS
Angel E
Courses Plus Student 2,581 Points

Forgot the return type before the function declaration ends and return the result from the parameter (function):

func mathOperation1(mathFunction: (Int, Int) -> Int, a: Int, b: Int) -> Int { return mathFunction(a, b) }