Scala--a new programming language--can be compared with Java and Ruby, but it has many improved features. A section of chapter 2 shows the differences between Scala and Java or Ruby. Scala can be run as a command line, as a script, or as a compiled program.

The book starts with instructions for installing Scala (chapter 1), and then provides simple programming examples (chapter 2). Most of the book consists of programming examples and their results. Scala uses lists to build immutable data structures (chapter 3), which improve thread safety. Functions can be passed as parameters (chapter 4). Chapter 5 describes pattern matching, which is a big extension of the Java switch statement. Chapter 6 is about the use of Scala actors, as a way to solve concurrency problems. This is a better solution than the Java synchronized keyword. Chapter 7 shows that Scala is better than other languages for writing libraries, because the application programming interfaces (APIs) are safer to use. Scala also has strong support for parsing (chapter 8). The book shows how to write a parser from ECMAScript to JavaScript Object Notation (JSON). A big advantage for team integration is that Scala compiles to Java Virtual Machine (JVM) bytecode and works with Java libraries; this way, some members of a Java team can start to write in Scala, without impacting the integration (chapter 9).

The presentation throughout the book is lighthearted; Pollak shows, in a humorous way, how he feels when he programs something in Scala, compared to other languages. The last sentence of the book states that “Scala makes it easier for coders to implement architecturally solid design than does Java or Ruby.”

This is a very interesting book about many aspects of programming and their implementation in Scala.