On Fri, Dec 5, 2008 at 8:02 AM, Ingmar Kliche <[EMAIL PROTECTED]> wrote: > Rahul, > > the latest SCXML WD [1] describes a set of system variables which are > read-only for the application. See section 5.5 [2]: "The Data Module > maintains a protected portion of the data model containing information that > may be useful to applications...." > > This could be implemented in commons-scxml using an additional context and > set it as the parent of the current root context. Some expression languages > (such as ECMAScript) support scope chains and allow to attach scopes read > only. <snip/>
We may need to abstract out the notion of a partitioned root context, just like we have a notion of ordinary context. > Other expression languages may require a special treatment of this > "system variable context". In this case it could be necessary to implement a > special context which handles the read-only behavior. > <snap/> Yes, its read-only in a limited sense (for the application developer i.e. within the SCXML document -- not for the implementation i.e. _event for example keeps changing with each event so the executor needs to be able to write to it). > At the same time we could change the "eventname" and "eventvalue" variables > to "_event.name" and "_event.value". > <snip/> Yeah, that needs to be done (though I think you mean "_eventdata" instead of "eventvalue"). If you feel like it, do open a JIRA issue to track this for the next release. -Rahul > What do you think? > > - Ingmar. > > [1] http://www.w3.org/TR/2008/WD-scxml-20080516/ > [2] http://www.w3.org/TR/2008/WD-scxml-20080516/#SystemVariables > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
