Kotlin 1.9

Kotlin.kt

package com.vivint

enum class Color(val code: Long) {
    RED(0xff0000L),
    GREEN(0x00ff00L),
    BLUE(0x0000ffL)
}

fun main() {
    // 1. Stable replacement of the enum class values function
    Color.values().forEach { println(it.code) } // This is not stable
    Color.entries.forEach { println(it.code) }  // This is stable 

    // 2. Stable ..< operator for open-ended ranges
    for (number in 2 until 10) {
        print("$number ")
    }
    for (number in 2..<10) {    // This is stable and replaces 2 until 10
        print("$number ")
    }

    // 3. New common function to get regex capture group by name
    val regex = """\b(?<city>[A-Za-z\s]+),\s(?<state>[A-Z]{2}):\s(?<areaCode>[0-9]{3})\b""".toRegex()
    val input = "Coordinates: Austin, TX: 123"
    val match = regex.find(input) ?: return
    println(match.groups["city"]?.value)        // -> Austin
    println(match.groups["state"]?.value)       // -> TX
    println(match.groups["areaCode"]?.value)    // -> 123
}