Return multiple values from a function in swift

Question

How do I return 3 separate data values of the same type(Int) from a function in swift?

I'm attempting to return the time of day, I need to return the Hour, Minute and Second as separate integers, but all in one go from the same function, is this possible?

I think I just don't understand the syntax for returning multiple values. This is the code I'm using, I'm having trouble with the last(return) line.

Any help would be greatly appreciated!

func getTime() -> Int
{
    let date = NSDate()
    let calendar = NSCalendar.currentCalendar()
    let components = calendar.components(.CalendarUnitHour | .CalendarUnitMinute | .CalendarUnitSecond, fromDate: date)
    let hour = components.hour
    let minute = components.minute
    let second = components.second
    let times:String = ("\(hour):\(minute):\(second)")
    return hour, minute, second
}

The "Swift Programming Language" iBook actually has a section titled "Functions with Multiple Return Values" ... — Martin R
– Martin R, Commented Dec 17, 2014 at 17:53

David Berry · Accepted Answer · 2014-12-17 17:22:21Z

375

Return a tuple:

func getTime() -> (Int, Int, Int) {
    ...
    return ( hour, minute, second)
}

Then it's invoked as:

let (hour, minute, second) = getTime()

or:

let time = getTime()
println("hour: \(time.0)")

answered Dec 17, 2014 at 17:22

David Berry

41.3k12 gold badges87 silver badges96 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

David Berry Over a year ago

Note that a better solution might be to define a Time struct and use that instead of the tuple.

phil Over a year ago

How would you call that swift func from an objective C method? Curious how you would gain a handle to three returned values. Would you use a dictionary, for example?

David Berry Over a year ago

You wouldn't. If you want to call it from objc you have to return a class (maybe a struct) not sure.

Bruno Lemos Over a year ago

It's recommended to add name to the parameters: func getTime() -> (hour: Int, minute: Int,second: Int) Then get like getTime().hour

David Berry Over a year ago

@BrunoLemos eh, I'm still going to go with the better solution is to define a Time struct and use that.

|

jtianling · Accepted Answer · 2015-07-30 12:37:23Z

89

Also:

func getTime() -> (hour: Int, minute: Int,second: Int) {
    let hour = 1
    let minute = 2
    let second = 3
    return ( hour, minute, second)
}

Then it's invoked as:

let time = getTime()
print("hour: \(time.hour), minute: \(time.minute), second: \(time.second)")

This is the standard way how to use it in the book The Swift Programming Language written by Apple.

or just like:

let time = getTime()
print("hour: \(time.0), minute: \(time.1), second: \(time.2)")

it's the same but less clearly.

edited Jul 30, 2015 at 12:37

answered Jul 30, 2015 at 12:21

jtianling

2,00716 silver badges19 bronze badges

6 Comments

Eric Aya Over a year ago

the right answer can't compile right in swift 2.0: wrong, returning an unnamed tuple in Swift 2 works the same as with Swift 1. See this screenshot.

jtianling Over a year ago

yes, you are right , but I get a compile error in a similarity context. I should find it why.

Eric Aya Over a year ago

The compile error was not related, it was because of the CalendarUnit format having changed in Swift 2, not the tuple format.

jtianling Over a year ago

Not like that, the compile error I talked about was appear in the code myself.

Lal Krishna Over a year ago

time.hour won't work anymore. Please update the code.

|

nabu · Accepted Answer · 2016-06-16 11:57:39Z

15

you should return three different values from this method and get these three in a single variable like this.

func getTime()-> (hour:Int,min:Int,sec:Int){
//your code
return (hour,min,sec)
}

get the value in single variable

let getTime = getTime()

now you can access the hour,min and seconds simply by "." ie.

print("hour:\(getTime.hour) min:\(getTime.min) sec:\(getTime.sec)")

answered Jun 16, 2016 at 11:57

nabu

5725 silver badges16 bronze badges

Comments

Hardik Thakkar · Accepted Answer · 2017-09-04 12:04:05Z

10

Swift 3

func getTime() -> (hour: Int, minute: Int,second: Int) {
        let hour = 1
        let minute = 20
        let second = 55
        return (hour, minute, second)
    }

To use :

let(hour, min,sec) = self.getTime()
print(hour,min,sec)

answered Sep 4, 2017 at 12:04

Hardik Thakkar

16k2 gold badges100 silver badges84 bronze badges

Comments

Harjot Singh · Accepted Answer · 2018-07-19 12:26:34Z

8

Update Swift 4.1

Here we create a struct to implement the Tuple usage and validate the OTP text length. That needs to be of 2 fields for this example.

struct ValidateOTP {
var code: String
var isValid: Bool }

func validateTheOTP() -> ValidateOTP {
    let otpCode = String(format: "%@%@", txtOtpField1.text!, txtOtpField2.text!)
    if otpCode.length < 2 {
        return ValidateOTP(code: otpCode, isValid: false)
    } else {
        return ValidateOTP(code: otpCode, isValid: true)
    }
}

Usage:

let isValidOTP = validateTheOTP()
    if isValidOTP.isValid { print(" valid OTP") } else {   self.alert(msg: "Please fill the valid OTP", buttons: ["Ok"], handler: nil)
    }

Hope it helps!

Thanks

answered Jul 19, 2018 at 12:26

Harjot Singh

6,9272 gold badges41 silver badges35 bronze badges

1 Comment

Harjot Singh Over a year ago

For better understanding: medium.com/@abhimuralidharan/tuple-in-swift-a9ddeb314c79

Dhaval Nimavat · Accepted Answer · 2018-07-12 05:05:48Z

1

//By : Dhaval Nimavat
    import UIKit

   func weather_diff(country1:String,temp1:Double,country2:String,temp2:Double)->(c1:String,c2:String,diff:Double)
   {
    let c1 = country1
    let c2 = country2
    let diff = temp1 - temp2
    return(c1,c2,diff)
   }

   let result = 
   weather_diff(country1: "India", temp1: 45.5, country2: "Canada", temp2:    18.5)
   print("Weather difference between \(result.c1) and \(result.c2) is \(result.diff)")

answered Jul 12, 2018 at 5:05

Dhaval Nimavat

191 bronze badge

1 Comment

Dhaval Nimavat Over a year ago

Output : Weather difference between India and Canada is 27.0

Collectives™ on Stack Overflow

Return multiple values from a function in swift

6 Answers 6

7 Comments

6 Comments

Comments

Comments

1 Comment

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

7 Comments

6 Comments

Comments

Comments

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related