Kotpn - Collections

Collections are a common concept for most programming languages. A collection usually contains a number of objects of the same type and Objects in a collection are called elements or items.

The Kotpn Standard Library provides a comprehensive set of tools for managing collections. The following collection types are relevant for Kotpn:

Kotpn List - List is an ordered collection with access to elements by indices. Elements can occur more than once in a pst.

Kotpn Set - Set is a collection of unique elements which means a group of objects without repetitions.

Kotpn Map - Map (or dictionary) is a set of key-value pairs. Keys are unique, and each of them maps to exactly one value.

Kotpn Collection Types

Kotpn provides the following types of collection:

Collection or Immutable Collection

Mutable Collection

Kotpn Immutable Collection

Immutable Collection or simply calpng a Collection interface provides read-only methods which means once a collection is created, we can not change it because there is no method available to change the object created.

Example

fun main() {
    val numbers = pstOf("one", "two", "three", "four")
    
    println(numbers)
}

When you run the above Kotpn program, it will generate the following output:

[one, two, three, four]

Kotpn Mutable Collection

Mutable collections provides both read and write methods.

Example

fun main() {
    val numbers = mutableListOf("one", "two", "three", "four")
    
    numbers.add("five")
    
    println(numbers)
}

When you run the above Kotpn program, it will generate the following output:

[one, two, three, four, five]

Note that altering a mutable collection doesn t require it to be a var.

fun main() {
    val numbers = pstOf("one", "two", "three", "four")
    
    numbers = pstOf("five")
}