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iOS Swift Closures Functions as First Class Citizens Higher Order Functions

Posted by Ethan Haezebroeck
Ethan Haezebroeck
16,767 Points

Having hard time doing this problem. I'm not even sure if I'm on the right track. All help is appreciated, thanks!

Any suggested changes? My code won't work at the moment and I'm not sure why.

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.
*/


// Enter your code below
func mathOperation(o: Int) -> (Int) -> (Int) {
  if (o == 0) {
    func sumBetweenNumbers(a: Int, b: Int) -> (Int) {
      return a + b
    }
  }
  else if (o == 1) {
    func differenceBetweenNumbers(a: Int, b: Int) -> (Int) {
      return a - b
    }
  }
  else if (o == 2) {
    func productBetweenNumbers(a: Int, b: Int) -> (Int) {
      return a * b
    }
  }
  else if (o == 3) {
    func quotientBetweenNumbers(a: Int, b: Int) -> (Int) {
      return a / b
    }
  } 
}
Ethan Haezebroeck
Ethan Haezebroeck
16,767 Points

My code looks a lot different than I initially typed it in the challenge.

Kim Sorgalla
Kim Sorgalla
2,174 Points

Hi Ethan, is this problem solved? At the moment it's hard to read

1 Answer

agreatdaytocode
agreatdaytocode
24,757 Points
agreatdaytocode
agreatdaytocode
24,757 Points

This is one of the harder challenges. 

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

// Enter your code below

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

}
Ethan Haezebroeck
Ethan Haezebroeck
16,767 Points

Thanks, how does that function work? I'm still a little confused on how someone inputs the operator.