In these pages,\u00a0Scala Book\u00a0<\/i>provides a quick introduction and overview of the Scala programming language<\/a>. The book is written in an informal style, and consists of more than 50 small lessons. Each lesson is long enough to give you an idea of how the language features in that lesson work, but short enough that you can read it in fifteen minutes or less.<\/p>\n One note before beginning:<\/p>\n To begin reading, click the \u201cnext\u201d link, or select the\u00a0Prelude: A Taste of Scala\u00a0<\/i>lesson in the table of contents.<\/p>\n Our hope in this book is to demonstrate that Scala is a beautiful, modern, expressive programming language<\/a>. To help demonstrate that, in this first chapter we\u2019ll jump right in and provide a whirlwind tour of Scala\u2019s main features. After this tour, the book begins with a more traditional \u201cGetting Started\u201d chapter.<\/p>\n In this book we assume that you\u2019ve used a language like Java<\/a> before, and are ready to see a series of Scala examples to get a feel for what the language looks like. Although it\u2019s not 100% necessary, it will also help if you\u2019ve already downloaded and installed Scala so you can test the examples as you go along. You can also test these examples online with ScalaFiddle.io.<\/p>\n Before we jump into the examples, here are a few important things to know about Scala:<\/p>\n Ever since the book,\u00a0C Programming Language<\/i>, it\u2019s been a tradition to begin programming books with a \u201cHello, world\u201d example, and not to disappoint, this is one way to write that example in Scala: After you save that code to a file named\u00a0Hello.scala<\/i>, you can compile it with scalac: If you\u2019re coming to Scala from Java, scalac is just like javac, and that command creates two files:<\/p>\n These are the same \u201c.class\u201d bytecode files you create with javac, and they\u2019re ready to run in the JVM. You run the Hello application with the scala command: We share more \u201cHello, world\u201d examples in the lessons that follow, so we\u2019ll leave that introduction as-is for now.<\/p>\n\n
Chapter – 2\u00a0 Prelude: A Taste of Scala<\/h2>\n
2.1 Overview<\/h4>\n
\n
2.2 Hello, world<\/h4>\n
\nobject Hello extends App {
\nprintln(“Hello, world”)
\n}<\/p>\n
\n$ scalac Hello.scala<\/p>\n\n
\n$ scala Hello<\/p>\n2.3 The Scala REPL<\/h4>\n