Cannot pass task 2 : Function as first class citizens

Question

I typed 
 let difference = mathOperation(differenceBetweenNumbers, 4,2)
which works perfectly fine in xcode playground, but for some weird reason the code challenge won't accept this answer. Do you have any idea how to fix that?
Thanks in advance
``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
}
func mathOperation(someFunction:(Int, Int) -> (Int), a:Int, b:Int)->Int{
return someFunction(a,b)
}
// Enter your code below
let difference = mathOperation(differenceBetweenNumbers, 4,2)
// Enter your code below
```

agreatdaytocode · Accepted Answer

This works for me: You have -> (Int) 
change it to -> Int
```Swift
func mathOperation(someOperationFunc: (Int, Int) -> Int, a: Int, b: Int) -> Int {
    return someOperationFunc(a, b)
}
let difference = mathOperation(differenceBetweenNumbers, 26, 22)
```

Welcome to the Treehouse Community

Looking to learn something new?

Dawid Cedrych

Dawid Cedrych

Cannot pass task 2 : Function as first class citizens

1 Answer

agreatdaytocode

agreatdaytocode

Dawid Cedrych

Dawid Cedrych

agreatdaytocode

agreatdaytocode