Function with Swift

Question

I am very new to Swift, actually I started learning it today. Can someone tell me whats wrong with calling the function in this way?

func myAddition(i:NSInteger,j:NSInteger) ->NSInteger {
    i
    j
    return i+j
}

myAddition(5, 6)

Edit I fixed the error by inserting j:

myAddition(5, j: 6)

is this normal? I am following a tutorial and there its working without j

You don't need `NSInteger` for such simple operations. Use an `Int` instead. — Eric Aya, Jun 20 '16 at 10:34
are you getting error while calling this? if yes then what is it? — Jigar Tarsariya, Jun 20 '16 at 10:37
[Swift Programming Series (iBooks Store)](https://itunes.apple.com/us/book-series/swift-programming-series/id888896989?mt=11) — Desdenova, Jun 20 '16 at 10:37
@vacawama They're probably using a Playground. Doing this displays the variable values in the side panel. — Eric Aya, Jun 20 '16 at 10:37
I changed it to Int, still the same problem. @vacawama I am using a Playgroun, I wanted to see the value of i and j — User1932, Jun 20 '16 at 10:39
@EricD, thanks. I use Playgrounds all the time, but I guess my *old school* mindset prevented me from seeing the use of variables that are accessed but "not used". — vacawama, Jun 20 '16 at 10:57

score 0 · Answer 1 · answered Jun 20 '16 at 10:40

0

You have to call method in this way:

 myAddition(5, j: 6)

Try this it may help you.

answered Jun 20 '16 at 10:40

Bhumika

876
7
20

Thank you it works but can you explain me why? In the tutorial its working without the j: – User1932 Jun 20 '16 at 10:42
@User1932 Visit this link it will help you to understand. http://stackoverflow.com/questions/24045890/why-does-a-function-call-require-the-parameter-name-in-swift – Bhumika Jun 20 '16 at 10:52

score 0 · Answer 2 · answered Jun 20 '16 at 10:41

0

func myAddition(i:Int,j:Int) ->Int {
    return i+j
}

print(myAddition(5, j: 6))

This will work for you.

answered Jun 20 '16 at 10:41

onemillion

682
5
19

Steve Ives · Accepted Answer · 2016-06-20T10:57:33.647

0

If you want to be able to call the function without specifying the parameter names, then you have to tell Swift that there are no external parameter names for the function by using the underbar (_) as the external parameter name:

func myAddition(_ i:NSInteger, _ j:NSInteger) -> NSInteger {
    return i+j
}

myAddition(5, 6)

Do you really need an NSInteger as opposed to a normal Swift Int:

func myAddition(_ i:Int , _ j:Int) -> Int {
    return i+j
}

myAddition(5, 6)

edited Jun 20 '16 at 10:57

answered Jun 20 '16 at 10:42

Steve Ives

7,894
3
24
55

I think the need to specify the first parameter name on the function call has changed between different versions of Swift , which is why you might not be seeing the same results as the tutorial. – Steve Ives Jun 20 '16 at 10:56

Function with Swift

3 Answers3