Hello all in C we have Tuple class a helper class to make ea kotlinlang #getting-started

var (x, y) = Tuple.Create("hello", "world");
// or
var (x, y) = ("hello", "again");
// or also
var x = ("hello", "again");
x.Item1 // hello
x.Item2 // again
// or also also
var x = (Xpto: "Hello", Yup: "Again")
x.Xpto 
x.Yup

in Kotlin I had read about destructors and find the Pair class Is it the equivalent? And is it possible initialise "Pair" on the fly like C#?

Ruckus

03/24/2021, 3:37 PM

You can use

to

to make a `Pair`:

val (x, y) = "hello" to "again"

val x = "hello" to "again"
x.first
x.second

There's also a

Triple

class, but Kotlin does not have tuples, so you cannot create arbitrary sizes or use custom keys.

diego.brum

03/24/2021, 3:39 PM

Nice, tks 🙂

Casey Brooks

03/24/2021, 3:43 PM

ad-hoc objects can be helpful intermediate types for data processing, where you may have been using tuples before https://kotlinlang.org/docs/object-declarations.html#object-expressions

diego.brum

03/24/2021, 3:47 PM

NIce one! Tks 🙂

Ruckus

03/24/2021, 4:16 PM

Wow, I've been using Kotlin for years and wasn't aware of that (the object expression without super types working privately). Thanks for the pointer.

Jordan Foo

03/24/2021, 4:40 PM

Also @diego.brum, typeAliases can make it cleaner to read and use

typealias MyPair = Pair<String, Int>

and

val myPair: MyPair = "myString" to 1
val (myString, myInt) = myPair

❤️ 2

Helps for when you're using a pair as a composite key for maps, for example (which is valid because the pair implementation is a data class, which overwrites equals and hashcode)

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