Issue - 295 - Create new type for variable names

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Issue - 295 - Create new type for variable names

Status: received
Date added: 5 Jun 2006
Date submitted: 05 June 2006
Submitter: Mark Ford
Description: Variable names are currently restricted to being NCNames with the further restriction that the "." character is disallowed. This is made explicit in the following paragraph in Section 8.1:

> Variable names are NCNames (as defined in XML Schema specification) but in addition they MUST NOT contain the “.” character.  This restriction is necessary because the “.” character is used as a delimiter in WS-BPEL's default binding to XPath 1.0  (i.e. the binding identified by "urn:oasis:names:tc:wsbpel:2.0:sublang:xpath1.0"). The delimiter separates the WS-BPEL message type variable name and the name of one of its WSDL message parts. The concatenation of the WSDL message variable name, the delimiter and the WSDL part name is used as an XPath variable reference which manifests the XML Infoset of the corresponding WSDL message part.

This restriction should be made explicit by creating a custom type in the schema that derives from NCName with the restriction that the "." character is not allowed (this is possible through a pattern or some similar mechanism). This change should also apply to any implicit variables that are created through constructs like the forEach's counterName and <fromPart> constructs nested within an onEvent.

In the absence of this proposal, we essentially have a discrepancy between the schema and the specification text. Granted, the specification text is the winner in such discrepancies but this issue could be resolved pretty easily by making a small change to the schema.

Note: this will affect the current static analysis document since it would remove the need for checking for the "." character in association with variable names since it would be something that could be accomplished through standard schema validation. It also avoids having to add checks for validating the counterName attribute of a forEach or the value of the toVariable attribute on a <fromPart>
Changes: 5 Jun 2006 - new issue

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