Subj : Can not use RegExp with sealed shared top scope
To   : netscape.public.mozilla.jseng
From : k0t1k@mac.com
Date : Wed Jul 06 2005 06:13 pm

I am trying to use shared top scope in the way suggested
http://www.mozilla.org/rhino/scopes.html

    top_scope = cx.initStandardObjects( null, false );
    ...
    loading some shared JS variables/functions
    ...
    top_scope.sealObject();

Then I am creating multiple scopes like this

    scope = (ScriptableObject)cx.newObject( top_scope );
    scope.setPrototype( top_scope );
    scope.setParentScope( null );

>From this point on, I can load/execute any JS using scope object,
unless these scripts are using RegExp.  If I am trying to create RegExp
variable ( for example something like this : 'var re1 = new RegExp(
"/>(?:\s+)</g" );' ) I am getting following exception:

org.mozilla.javascript.EvaluatorException: Cannot modify a property of
a sealed object: RegExp. (filter::removeSpacesFilter#1)
	at
org.mozilla.javascript.DefaultErrorReporter.runtimeError(DefaultErrorReporter.java:95)
	at org.mozilla.javascript.Context.reportRuntimeError(Context.java:966)
	at
org.mozilla.javascript.Context.reportRuntimeError(Context.java:1022)
	at
org.mozilla.javascript.Context.reportRuntimeError1(Context.java:985)
	at
org.mozilla.javascript.ScriptableObject.put(ScriptableObject.java:231)
	at
org.mozilla.javascript.IdScriptableObject.put(IdScriptableObject.java:415)
	at
org.mozilla.javascript.ScriptableObject.defineProperty(ScriptableObject.java:1000)
	at
org.mozilla.javascript.ScriptableObject.defineProperty(ScriptableObject.java:1019)
	at
org.mozilla.javascript.regexp.NativeRegExp.init(NativeRegExp.java:153)
....

Could some one please shed some light to this problem?  Why RegExp
(function/class?) needs to have one of its properties modified each
time you are creating new instance of it?

.