Learning ActionScript 3.0, 2nd Edition

Chapter 2. Core Language Fundamentals

IN THIS CHAPTER

Jump Right In

Miscellaneous Basics

Variables and Data Types

Operators

Conditionals

Loops

Arrays

Vectors

Functions

Custom Objects

this and parent

Absolute Versus Relative Addresses

Put It All Together

What’s Next?

ActionScript 3.0 is a complete rewrite of the language—so much so that ActionScript 3.0 doesn’t even share the same Flash Player code base as prior versions of ActionScript. But that’s all behind the scenes. The truth is that all versions of ActionScript to date have quite a bit in common. This is because ActionScript is based on a scripting language standard (called ECMA-262) that grew from the success of JavaScript, and ongoing versions of ActionScript are as backward-compatible as possible in an effort to support legacy projects.

Of course, each new update to ActionScript introduces new features and, because the decision was made to create ActionScript 3.0 from scratch, an opportunity presented itself to tidy up a few messy things that lingered from previous versions. Among these improvements are tightening up and requiring best practices that had been optional, and restructuring how events and graphical assets are handled (the Event Model and Display List, respectively). All of this progress, however, didn’t steamroll over the standard upon which ActionScript is based, and most of the language fundamentals remain intact.

With the intention to focus on new ActionScript 3.0 features later on, we want to cover some of the more commonly ...