scala-code-along

A short intro to Scala.

The provided code is ment as inspiration for interactive live coding sessions lead by someone who wants to share the joy of Scala. We code-along together step-by-step by typing/pasting code snippets into the Scala interactive shell, also known as the Scala REPL.

Preparations before coding along:

• Download latest Scala using http://scala-lang.org/download/ or mirrors provided below by LTH, Lund University in Sweden.
• Open a terminal window (bash | powershell | cmd)
• Run the scala command
• Type or paste these code snippets line by line as we code along together

Scala download mirrors at cs.lth.se

• Scala command line tools (scala, scalac, scaladoc, etc)

  • Scala 2.11.6 Windows msi 110MB
  • Scala 2.11.6 Unix/MacOSX tgz 27MB
  • Scala 2.11.6 Linux/Debian deb 78MB

• Kojo IDE for easy scripting with api for 2D graphics and simple game dev

  • Kojo 2.4.06 Windows exe 18MB
  • Kojo 2.4.06 MacOSX dmg 39MB
  • Kojo 2.4.06 Linux/Unix jar 18MB

• Recommended reading for java programmers:

  • [Part of "Scala for the impatient"] (http://fileadmin.cs.lth.se/scala/scala-impatient.pdf) 6MB, first 110 pages Copyright Cay S. Horstmann 2012.

• Download SimpleWindow etc. in cs_eda016.jar 51kB and JavaDoc for cs_eda016 to test Java interoperability:

  • put the jar on the REPL's class path with scala -cp cs_eda016.jar
  • or if you have compiled some object Main extends App that import se.lth.cs.window.SimpleWindow, run your class file Main.class using:
    • Windows: scala -cp "cs_eda016.jar;." Main note the quotes, semicolon and dot
    • Linux: scala -cp "cs_eda016.jar:." Main note the quotes, colon and dot

What is Scala?

• Scala is a statically typed object-functional programming language
• Scala runs as fast as Java on the Java Virtual Machine
• Scala can call any Java byte code, including all classes in the JDK
• Scala's standard library includes a powerful collections library
• Scala has more powerful abstraction mechanisms compared to Java
• Scala is more regular compared to Java
• Scala is as concise as many dynamic scripting languages
• Scala is statically typed; thus both safe and fast
• Scala is used by Twitter, LinkedIn, Netflix, Coursera, ...
• There are many useful Scala libs and frameworks: Play, Akka, Scalatra, ...