A Scala 3 “Hello, world” Example (Video)
This is a little out of order, but I want to create a small, sample application to show how easy this is with Scala 3 and scala-cli
:
- Use Terminal and VS Code
- Create the app
- Compile and run with
scala-cli
A first example app
- Earlier i showed how to create a function/method:
def double(i: Int): Int = i * 2
- The way S3 works is that you annotate any method with @main to make it a “main method”. Your application starts here, and it’s called the “entry point” to your application:
// Hello.scala
@main def hello() =
println("Hello, world")
Compile and run with scala-cli
:
$ scala-cli Hello.scala
A second example app
// Hello2.scala
@main def hello(name: String) =
println("Hello, " + name)
Run everything in the current directory with scala-cli
:
$ scala-cli .
Purpose of all this
- Show some simple applications
- Show how to run them with
scala-cli
Update: All of my new videos are now on
LearnScala.dev