Subj : Re: Read-only variables ....
To   : Bruno Vignola <bvignola@hotmail.com>
From : Igor Bukanov <igor@fastmail.fm>
Date : Mon Dec 15 2003 04:59 pm

Bruno Vignola wrote:
> Hi all! 
> 
> I am a new rhino user, so I am sorry if my questions
> are trivial but I was not able to find anything in the
> docs so far ...
> 
> - It is possible to define "read-only" variables?

You can not do it from JavaScript as Rhino does not support const 
keyword as SpiderMonkey (Mozilla JS engine) does. From Java you can add 
ScriptableObject.READONLY flag when calling 
Scriptable.Object.defineProperty() to create read-only properties. Note 
that a variable is just a property of a scope object.

> 
> - Furthermore, it is possible to list the content of 
>   a context? Is there any method for doing this job?

You are confusing Context instances and scope objects. Context instances 
do not store any script data, it is scopes and other instances of 
Scriptable that do. See http://www.mozilla.org/rhino/scopes.html for 
details.

To get enumeratable properties (i.e. ones that "for (i in object)" will 
enumerate) stored in Scripatble instance, use Scriptable.getIds(). To 
get all properties, check if Scripatble instance also implements 
org.mozilla.javascript.debug.DebuggableObject which contains getAllIds 
method to get all properties.

Regards, Igor

.