Kotlin · Course navigation

Kotlin Basics

Use values and string templates.

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The concept

val creates a read-only reference. main is the program entry point. A string template inserts the current value into text.

Kotlin

fun main() {
    val name = "Ada"
    println("Hello, $name")
}

Output

Hello, Ada

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1fun main() {

2 val name = "Ada"

3 println("Hello, $name")

4}

Start to inspect the source, values, and output. These prepared steps explain the published sample; grouped loop steps describe multiple iterations.

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Prepared trace of the published program. Some rows group repeated iterations.
Step / line	What happens	State after step	Output so far
	Bind Ada to a read-only name.	`name = "Ada"`	—
	Insert name into the string template and print.	`name = "Ada"`	Hello, Ada

How Kotlin processes this code

Kotlin commonly compiles to JVM bytecode, which the JVM executes.