14.4. Reserved Words
Some reserved words are used by the ActionScript interpreter to denote specific built-in language features such as statements and operators. They are reserved for use by the interpreter, and we must avoid using them as identifiers in our code. Using a reserved word for a purpose other than its reserved internal purpose causes an error in most cases. The reserved words of ActionScript are listed in Table 14-1.
Table 14-1. ActionScript's Reserved Words
|
add* |
for |
lt* |
tellTarget* |
|
function |
ne* |
this |
|
|
break |
ge* |
new |
typeof |
|
continue |
gt* |
var |
|
|
delete |
if |
on |
void |
|
do |
ifFrameLoaded* |
onClipEvent |
while |
|
else |
in |
with |
|
|
eq* |
le* |
return |
* Flash 4 reserved words deprecated in Flash 5.
You should also try to avoid using the keywords listed in Table 14-2. They are not part of ActionScript in Flash 5 but may become a part of the language in the future because they are slated for potential use by ECMA-262.
Table 14-2. Potential Future Reserved Words
In addition to the formally defined keywords, you should also avoid using the names of built-in properties, methods, and objects as identifiers in your code. Doing so overrides the default behavior of the property, method, or object in question. For example:
Date = new Object( ); // Oops! We just disabled the Date( ) constructor
Now we can no longer create Date objects:
var now = new Date( ); // Sets now to undefined trace(now); // Displays the empty string, not the current time and date
 |  |  |
| 14.3. Comments |  | 14.5. Identifiers |
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