ActionScript for Flash MX: The Definitive Guide, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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on (release) { // No semicolon here

trace("Click"); // Semicolon here

} // No semicolon here

However, the semicolon is mandatory following a function literal:

function (param1, param2, ... paramn) { statements };

The special #include directive, and the #initclip and #endinitclip pragmas should

not be followed by a semicolon and will cause an error if used with one. For correct

usage, see the Language Reference.

Comments

So-called comments are text that is ignored by the interpreter but entered by the pro-

grammer specifically for the benefit of humans reading the code. Comments should

be used liberally to explain what the code does, provide version control information,

or describe other relevant information, such as how a data structure is being used or

why certain programming choices were made. Comments should describe your code

at the conceptual level, not merely mirror the syntax of the code itself. For example,

the following comment is useless:

// Set x equal to 5

var x = 5;

whereas the following comment tells us why we’re setting x to 5, which helps us fol-

low the flow of the code:

// Initialize our player's x position

var x = 5;

Note that you can go a long way toward making your code “self-commenting” by

using descriptive variable names and handler names. Consider which ...