New issue with possible solution - Unbound free variables

• From: Steve Ross-Talbot <steve@enigmatec.net>
• Date: Tue, 12 Oct 2004 13:46:54 +0100
• To: WS-Choreography List <public-ws-chor@w3.org>, public-ws-chor-comments@w3.org
• Message-Id: <CBB11CAD-1C4C-11D9-8308-000393D13C9A@enigmatec.net>

If a "free" variable in an enclosed choreography is not BOUND then what 
is the variables status? Does it have a value or is it said to be 
undefined? My concern is if any conditional logic is based on the value 
of a free variable that is UNBOUND it may have unexpected consequences.

One possible solution is to add a default value to the definition of 
the variable within the choreography in which it is defined. The 
semantics would be such that free variables that are not bound take on 
the default value. The absence of a default value for a free variable 
that is UNBOUND would result in a type error or a warning being 
generated on parsing the CDL file(s) in which it is defined.

At alternative would be to have no default value and simply add the 
necessary text (above) so that it is made clear how to parse a CDL 
document and what to report as an error or warning.

Cheers

Steve T

Received on Tuesday, 12 October 2004 12:47:09 UTC