- From: <bugzilla@wiggum.w3.org>
- Date: Wed, 01 Aug 2007 03:03:38 +0000
- To: www-xml-schema-comments@w3.org
- CC:
http://www.w3.org/Bugs/Public/show_bug.cgi?id=4903 Summary: Clarify or remove conformance language relating to document instances Product: XML Schema Version: 1.0/1.1 both Platform: Macintosh OS/Version: All Status: NEW Severity: normal Priority: P2 Component: Structures: XSD Part 1 AssignedTo: cmsmcq@w3.org ReportedBy: cmsmcq@w3.org QAContact: www-xml-schema-comments@w3.org Section 3.2.1 of Structures reads in part: The value of the attribute MUST conform to the supplied {type definition}. I am not sure what this sentence means. MUST is defined in section 1.5 of the spec (Documentation Conventions and Terminology) as describing requirements for conformance: Conforming documents and XSDL-aware processors are required to behave as described; otherwise they are in error. The implication seems to be that section 3.2.1 is defining a rule which XML instance documents must obey in order to conform to the XSDL spec, and a further implication would be that XML instance documents can usefully be spoken of as conforming, or not conforming, to our spec. I don't think XML instance documents are usefully regarded as conforming or not conforming to the XSDL spec. I think that this and other instances (there are some) of similar usages are describing the conditions under which document instances are valid against (or conform to) a particular schema, not conditions under which they conform to XSDL. Two changes should be made: (1) every sentence that uses conformance-related terminology of XML document instances other than schema documents should be revised to refer to validity not conformance, and (2) the conformance section of the spec should explicitly state that validators and schema documents can conform to the XSDL spec, and that document instances can conform to a schema (by being valid against it) but not to XSDL. Another paragraph in 3.2.1 causes even more difficulties. The {name} property [of an Attribute Declaration] MUST match the local part of the names of attributes being validated. What does this mean? If a schema contains an Attribute Declaration whose local name matches no attributes in the document instance, then the {name} property of the Attribute Declaration has clearly not matched the local part of the names of any attributes being validated. That is, this rule, as formulated, has not ben obeyed. Is the schema then not a conforming schema? Is the processor which performed the match not a conforming processor? If this sentence can be interpreted plausibly and given meaning in its current formulation, then something needs to be added to the spec to make that interpretation accessible to readers (including members of the XML Schema WG). Otherwise, this sentence and others which misuse conformance-related terms should be recast to say what they mean. (In this case, I believe the intended meaning to be that the governing attribute declaration for an attribute information item is found in part on the basis of the attribute's extended name matching the target namespace and {name} of the declaration. Perhaps "The {name} and {target namespace} property of the Attribute Declaration are used to associate the declaration with attributes being validated.")
Received on Wednesday, 1 August 2007 03:03:49 UTC