Issue - 266 - Clarification needed on extensibleAssign

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Issue - 266 - Clarification needed on extensibleAssign

Status: received
Date added: 14 Apr 2006
Date submitted: 13 April 2006
Submitter: Mark Ford
Description: Section 5 introduces the two explicit extension contructs: <extensibleAssign> and <extensionActivity>. There is a statement that says specific rules for these constructs are described in sections 8.4 and 10.9.

The issue is that there are no specific rules for extensibleAssign. In particular, what to do if the processor does not understand the extension and it was declared with mustUnderstand="no". My assumption is that the assign activity would skip over the extensibleAssign as if it wasn't there. This should be made explicit in the specification text since we make reference to rules that aren't present.
Submitter's proposal:

Change the first paragraph in Section 8.4

FROM:

> The <assign> activity can be used to copy data from one variable to another, as well as to construct and insert new data using expressions. The use of expressions is primarily motivated by the need to perform simple computation (such as incrementing sequence numbers). Expressions operate on variables, properties, and literal constants to produce a new value. The <assign> activity can also be used to copy endpoint references to and from partnerLinks. Finally, it is possible to include extensible data manipulation operations defined as extension elements under namespaces different from the WS-BPEL namespace. 
TO: 
> The <assign> activity can be used to copy data from one variable to another, as well as to construct and insert new data using expressions. The use of expressions is primarily motivated by the need to perform simple computation (such as incrementing sequence numbers). Expressions operate on variables, properties, and literal constants to produce a new value. The <assign> activity can also be used to copy endpoint references to and from partnerLinks. It is also possible to include extensible data manipulation operations defined as extension elements under namespaces different from the WS-BPEL namespace. If the element contained within the extensionAssign element is not recognized by the WS-BPEL processor and is not subject to a mustUnderstand="yes" requirement from an extension declaration then the extensibleAssign MUST be treated as if it were not present (See section 12.7 Extension Declarations).

Changes: 14 Apr 2006 - new issue

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