How to write hello world

Objective

I want to write a hello world program in Scala, and run it.

Steps

1. Create a fresh directory, like hello_scala/
2. Create a directory named project/ under hello_scala/, and create project/build.properties with

   sbt.version=2.0.0-M3
   

3. Under hello_scala/, create build.sbt:

   scalaVersion := "3.3.3"
   

4. Under hello_scala/, create Hello.scala:

    @main def main(args: String*): Unit =
      println(s"Hello ${args.mkString}")
   

5. Navigate to hello_scala/ from the terminal, and run sbt:

   $ sbt
   

6. When the prompt appears, type run:

   sbt:hello_scala> run
   

7. Type exit to exit the sbt shell:

   sbt:hello_scala> exit
   

Alternatives

When you're in a hurry, you can run sbt init in a fresh directory, and select the first template.