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iOS

Posted by Laurie Cai
Laurie Cai
5,391 Points

Nesting function in another function - why is my code not working?

  1. User inputs an integer
  2. Determine whether it's positive or negative
  3. Return "This number is positive" or "This number is negative"

I've started by writing an evaluateIfPositive boolean function that determines whether it's positive, then using that function inside the announcePositiveOrNegative function. 

func evaluateIfPositive(integer: Int) -> Bool {
    if integer < 0 {
        return false
    } else {
        return true
    }
}

func announcePositiveOrNegative(for userInput: Int) -> String {
    evaluateIfPositive(userInput) {
        if true {
            return "This number is positive"
        } else {
            return "This number is negative"
        }
    }
}

Error returned on this line: 

evaluateIfPositive(userInput) {

"Extra argument in call"

What am I doing wrong?

2 Answers

Abdullah Althobetey
Abdullah Althobetey
18,216 Points

Hi, Laurie. After you call evalutateIfPositive() you opened a block with {} this is why you get an error. You defined evalutateIfPositive to return a boolean value, so you should grab that value in a variable like so:

func evaluateIfPositive(integer: Int) -> Bool {
    if integer < 0 {
        return false
    } else {
        return true
    }
}

func announcePositiveOrNegative(for userInput: Int) -> String
{
    let result = evaluateIfPositive(integer: userInput)

    if result {
        return "This number is positive"
    } else {
        return "This number is negative"
    }
}

Also, note that you should type the argument label 'integer' when calling evaluteIfPositive() function.

Jeremy Conley
Jeremy Conley
4,791 Points
Jeremy Conley
Jeremy Conley
4,791 Points

The problem is the syntax, since your function returns a bool you check it like this

func evaluateIfPositive(integer: Int) -> Bool {
    if integer < 0 {
        return false
    } else {
        return true
    }
}

func announcePositiveOrNegative(for userInput: Int) -> String {
    if evaluateIfPositive(integer: userInput) == true {
        return "This number is positive"
    } else {
        return "This number is negative"
    }
}