Learn Kotlin- Destructuring Declarations


Destructuring Declarations

Destructuring Declarations is yet another important feature available in Kotlin. We can take advantage of this feature to write the better application.

What is Destructuring?

Destructuring is a convenient way of extracting multiple values from data stored in (possibly nested) objects and Arrays. It can be used in locations that receive data (such as the left-hand side of an assignment).

Sometimes it is convenient to destructure an object into a number of variables, for example:


val (name, age) = developer

Now, we can use name and age independently like below:


println(name)
println(age)

Use-cases where we can use the Destructuring feature:

  • Returning Two Values from a Function

Example


data class Developer(val name: String, val age: Int)
fun getDeveloper(): Developer {
 // some logic
 return Developer(name, age)
}


// Now, to use this function:
val (name, age) = getDeveloper()

  • Destructuring Declarations and Maps

Example


for ((key, value) in map) {
 // do something with the key and the value
}

So use this Destructuring feature, when it is required.