How to create Scala script

Hello World

Create HelloWorld.scala file with the following

object HelloWorld extends App {
    println("Hello World")
}

Compile it by

scalac HelloWorld.scala

Run it with:

scala HelloWorld

Read arguments

Once you have create an object that extends App, you can access arguments’ array with args.

object HelloWorld extends App {
    if (args.length == 0) {
        println("Hello World")
    } else {
        println("Hello " + args(0))
    }
}

Run it

scalac HelloWorld.scala
scala HelloWorld

What if I do not want to extend App?

Then you can implement main method

object HelloWorld {
    def main(args: Array[String]) = {
        println("Hello " + args(0))
    }
}

Script

You can also create script hello.sh

#!/usr/bin/env scala

println("Hello World")

Then you can simply run it with

chmod +x hello.sh
hello.sh

Updated 2018-07-30