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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Posted by Oguzhan Cetinkaya
Oguzhan Cetinkaya
2,172 Points

Here is my latest answer for task 2: let difference = mathOperation(differenceBetweenNumbers,3,5) What is the problem?

I cannot pass the exam. What's wrong?

higherOrderFunctions.swift 
func differenceBetweenNumbers(a: Int, b:Int) -> (Int) {
    return a - b
}

// Enter your code below
func mathOperation(aFunc:(Int, Int) -> (Int),firstInt:Int,secondInt:Int) -> (Int){
    return aFunc(firstInt,secondInt)
}

let difference = mathOperation(differenceBetweenNumbers,3,5)

2 Answers

Caleb Kleveter
MOD
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Use this code for the function, gets rid of some of the parentheses around the returns:

func mathOperation(anyAddFunc: (Int, Int) -> Int, a: Int, b: Int) -> Int{
    return anyAddFunc(a,b)
Oguzhan Cetinkaya
Oguzhan Cetinkaya
2,172 Points

Thank you, it worked :) It's about the compiler and some empty spaces issue I think..

Caleb Kleveter
MOD
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

I don't know that this code is any different but try copy and pasting it.

let difference = mathOperation(differenceBetweenNumbers, 2, 1)
Oguzhan Cetinkaya
Oguzhan Cetinkaya
2,172 Points

Unfortunately, it did not work. I cannot pass the Swift Closure exam because of this problem.