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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Chapter 5

CHAPTER 5

Operators

An operator is a symbol or keyword that manipulates, combines, or transforms data. If

you’re new to programming, you’ll notice that some mathematical operators, such as

+ (addition) and – (subtraction), are very familiar. In other cases, you’ll have to learn

special programming syntax, even if the concepts are familiar. For example, to multi-

ply two numbers, ActionScript uses the symbol * (the multiplication operator) instead

of the × typically taught in grade school. For example, this multiplies 5 times 6:

5 * 6;

General Features of Operators

Though each operator has its own specialized task, all operators share a number of

general characteristics. Before we consider the operators individually, let’s see how

they behave generally.

Operators and Expressions

Operators perform actions using the data values (operands) supplied. For example, in

the operation

5 * 6, the numbers 5 and 6 are the operands of the multiplication oper-

ator (*). The operands can be any kind of expression; for example:

total = player1score + bonusScore; // Operands are variables

answer = (x+y) - (Math.PI * radius * radius); // Operands are complex expressions

Observe in the second example that both the left and right operands of the – opera-

tor are expressions that themselves involve ...