Scala Lab

From Dev8D

Contents 1 Scala Lab 2 Organisers 3 Attending 4 Coding Dojos 5 Introduction 6 Resources 6.1 Books 6.2 Essential software bits

Scala Lab

#dev8d #lab

When:	Fri 26th 14:00-18:00
Where:	Coding_Lab
Twitter Tags:	#dev8d #lab

Organisers

• Tom Morris

Attending

If you are thinking of attending this session, you can add your name to the list below (places are limited):

• Tom Morris
• Damian Steer
• John Hoyland
• Ed Summers
• Tilaye Alemu
• Ianthe Hind
• Adrian Mouat
• Nasir Jamal
• Tom Smith
• Dan Hagon
• Ross McFarlane

Coding Dojos

The coding lab will be in the style of a 'Coding Dojo'.

If you would like to understand what a 'Coding Dojo' is, David Flanders has kindly put together this video:

[Principles behind Coding Dojos]

Introduction

Scala is a general purpose, practical, object-oriented/functional-hybrid programming language that runs on the JVM. It's type-safe and has a performance profile very similar to Java, but has the expressiveness of dynamic languages like Ruby and Python. Some Java users are treating it as a "power Java", some are using it as a scalable back-end for other applications (Twitter), some are using it as a half-way house between Java and Python/Ruby. In the workshop, we will look at some of the features of the language, learn the syntax and start using it to build something in a Coding Dojo.

To participate, it is strongly recommended that you download a recent version of the Scala compiler/runtime - 2.7 or 2.8 branch (the version installed by apt-get on Ubuntu or Debian Sid/Squeeze is fine). Familiarity with Java is useful; I've included code sample comparisons to Java, C#, Python and Ruby. For the Coding Dojo, we will be using SciTE on a Linux machine.

Resources

One thing to note: the Scala language is developed quite actively. Stuff changes: lots of stuff is going to change in the imminent 2.8 release. Be aware.

• Scala by Example describes most of the features of Scala
• Scala Tutorial for Java Programmers is useful - despite the title, it's useful for any programmers, not just Java programmers.
• The Code Commit blog has an excellent six part series called "Scala for Java refugees" - it's useful for non-Java programmers too:
  • Part 1: main
  • Part 2: Basic OOP
  • Part 3: Methods and Statics
  • Part 4: Pattern Matching and Exceptions
  • Part 5: Traits and Types
  • Part 6: Getting Over Java
• I maintain a little page called Scala for Hackers which is a sort of engineers log of how to do everyday web-hack type things with Scala - currently covers introspection, HTTP GET and parsing XML and JSON.
• Stack Overflow: Common programming mistakes for Scala developers to avoid
• SIDs - Scala Improvement Documents, the Scala equivalent of PEPs in Python
• Twitter on Scala - discusses some of the reasoning behind Twitter's decision to use Scala on the back-end.

Books

There are a number of Scala books available:

• Martin Odersky, Lex Spoon and Bill Venners, Programming in Scala - written by Scala's creator (Martin Odersky), this is a great book, but can be a bit academic at times.
• Alex Payne and Dean Wampler, Programming Scala - co-written by Alex Payne from Twitter (who have implemented Scala on the back-end of a very large production site). It's particularly useful as it covers features in the upcoming 2.8 release.
  • Interview with the authors on the On Ruby blog
  • You can read the 'rough cut' of the book online here.
• David Pollak, Beginning Scala - written by the author of the Lift web framework
  • Interview with the author on the On Ruby blog
• Venkat Subramaniam, Programming Scala: Tackle Multi-Core Complexity on the Java Virtual Machine - covers Scala's Actor-based concurrency system in some detail.

Essential software bits

• sbt: simple build tool for Scala - a lightweight alternative to using Ant/Maven. Uses Scala code for configuration rather than XML or makefiles.
• Unit testing: ScalaTest, Specs, Rehersal
• Vim syntax highlighting for Scala
• scala-vim-snippets (if you use snipMate, the TextMate snippets emulator for Vim, this adds all the snippets from the TextMate bundle and a few from the Java snippets file)
• Scala, emacs and yasnippet (if you use Emacs, try this)