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: Operators

where methodName is some method of the superclass and arg1,...argn is a list of

arguments passed to that method. Within the method, the

this keyword points to

the object whose class or method invoked the superclass method. Used in this man-

ner, the super operator is functionally equivalent to the following rather unwieldy

statement:

this.constructor.prototype.__proto__.constructor.apply(this, arguments);

For practical examples showing super in use, see “Making a Class” and “Accessing

overridden methods” in Chapter 12.

Note that super is not technically an operator. Rather, it is an identifier made avail-

able only during function execution, much like the

arguments object. ActionScript’s

super is not an implementation of ECMAScript v4’s super operator. Nevertheless, for

the sake of discussion, both Macromedia’s ActionScript Dictionary and this book cat-

egorize super with other operators.

The Function Call Operator

As we’ve seen with the trace() function and the string-manipulation functions, we

use the function call operator,

(), to invoke a function. A function call takes the gen-

eral form:

function_name(argument_list)

The first operand, function_name, is the name of some function and must be an iden-

tifier, not an expression. If the function does not exist, the ...