722 2004-05-21 17:51:34 +0000 Use of participants for scoping 2004-12-01 17:04:21 +0000 1 1 1 Unclassified WS Choreography Spec: Variables unspecified Other other RESOLVED DUPLICATE 846 http://lists.w3.org/Archives/Public/public-ws-chor-comments/2004May/0003.html P2 normal -- 724 1 gritzinger martin.chapman public-ws-chor-comments oldest_to_newest 1907 0 gritzinger 2004-05-21 17:51:34 +0000 In the current CDL specification (Web Services Choreography Description Language Version 1.0, W3C Working Draft 27 April 2004) the word 'participant' is used consistently in the text as the thing that exchanges information by exchanging messages (a described by the interaction elements) with other such things. However, a participant can consist of one or more roles (which represent one or more classes of behaviour) and therefore it is the 'Role' element that is used in the actual XML Choreography description schema and instance documents thereof. I suggest that a participant is defined as a set of one or more roles that can share variable data by 'assignment' rather than message passing, and that therefore a participant provides the scoping boundary for variable information sharing. If this change is agreed various parts of the specification may need to be amended and I have not found all those places. One place such place is 3rd paragraph of 2.3 'Coupling Web Service participants' which currently reads: Within a Choreography, information is always exchanged between Participants. This is arguably incorrect anyway as we definitely need a way of modelling the passing of information between roles within a participant. I suggest amending to something like: Within a Choreography, information is always exchanged by message passing using Interaction elements between Participants, and by sharing Variables or by assignment between Variables for information exchange between Roles within a Participant. The alternative approach would be to confine variable scope to only being that of a role and no wider at all and to use message passing (interaction) between roles within a participant as well as between roles in different participants. However, this means that participant rightly figures strongly as a modelling concept in the language model and text, but is not used or useful in the language itself. Best Regards Tony A M Fletcher 2221 1 martin.chapman 2004-09-02 15:41:58 +0000 hard to classify into an exitistong component as it touches on a number of areas. 2674 2 martin.chapman 2004-12-01 17:04:21 +0000 *** This bug has been marked as a duplicate of 846 ***