Re: Removing ambiguity regarding exceptions on record

Gary Brown wrote:

> In section 6.2.3, it says:
>
> "When two or more record elements are specified for the same roleType 
> in an
> interaction, with their causeException attributes set to indicate that an
> exception should be caused, then one of the exception types MAY be 
> caused.
> The throwing of an exception has a non-observable predicate condition 
> associated
> implicitly with it, that decides if an exception is caused"
>
> Due to the fact that this describes a non-observable predicate making 
> the decision about which (if any) of the multiple exceptions are 
> thrown, it means that it may be difficult for the other participants 
> to deterministically identify the same path through the choreography.
>
> I would suggest changing the sentence to prevent an exchange (or 
> timeout) having multiple records with exceptions (i.e. have atmost one 
> record with causeException set). A replacement sentence could be:
>
> "Two or more record elements, that are specified for the same roleType 
> in an interaction, with their causeException attribute set to indicate 
> that an exception should be caused, MUST not be permitted."
>
> OR
>
> "Where a roleType has multiple record elements associated with an 
> exchange or timeout, only one of these record elements MAY define a 
> causeException attribute".
>
mm1: Prefer the latter.

Received on Tuesday, 23 January 2007 19:35:26 UTC