- From: Dave Beckett <dave.beckett@bristol.ac.uk>
- Date: Thu, 17 May 2001 16:38:16 +0100
- To: w3c-rdfcore-wg@w3.org
Here is a second attempt at rewording previous things from earlier discussions and resolutions, firstly I'll review what we resolved First resolution interpretation 1) in http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/0035.html and second resolution items 1-4 http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/0036.html was agreed as recorded in the minutes of the 2001-05-11 meting: http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/att-0060/01-2001-05-11.html Summarising and rewording the above. I propose we resolve: 1. The current RDF/XML syntax uses the following attributes in the syntax (from my reference at http://www.redland.opensource.ac.uk/notes/concepts.html ) List of RDF attributes (henceforth The List) about aboutEach aboutEachPrefix ID bagID resource parseType li <_n> subject predicate object type value Discussion: ISSUE: I propose we do NOT add the remaining concepts: Seq Bag Alt Property Statement - these are rdfs:Class-es and can never be used as attributes RDF Description - syntax only things that have no current use as attributes 2. The grammar will be corrected to require namespace-qualification for all attributes for The List. A namespace prefix MUST be used for these attributes, where the namespace prefix points to the RDF URI http://www.w3.org/1999/02/22-rdf-syntax-ns# The meaning of the attributes is defined by the appropriate RDF M&S sections and is not modified here. The changes to the grammar at http://www.w3.org/TR/REC-rdf-syntax/#grammar include modifying productions 6.6, 6.7, 6.8, 6.9, 6.11, 6.18, 6.32, 6.33 to have rdf: added before all the attributes. There are almost certainly other changes to the grammar, as well as changes throughout the rest of the document such as examples and in-text mentions. 3. On input, processors MUST accept unprefixed attributes from The List on any elements. These attributes must be processed as if they were written with a prefix as defined in #2. 4. On output, processors MUST emit attributes from The List with a namespace prefix; where the prefix is defined as in #2. 5. The unprefixed attributes are deprecated and MAY be forbidden in future versions of the syntax. Discussion: We may suggest that processors could emit a warning on input optionally. 6. The grammar will be corrected to allow non-namespace qualified RDF elements (NOT attributes) when a default XML namespace is defined with an xmlns="..." attribute. Discussion: For example <Description xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"> ... </Description> is currently forbidden by production 6.3; it requires rdf:Description 7. Unprefixed attributes not on The List have no meaning in RDF and MUST NOT be used to generate statements. Processors MUST also skip the element containing such attributes and generate no statements for the entire XML element and content. Discussion: This is consistent with existing words in RDF M&S describing actions when unknown rdf: attributes are found: [[ When an RDF processor encounters an XML element or attribute name that is declared to be from a namespace whose name begins with the string "http://www.w3.org/TR/REC-rdf-syntax" and the processor does not recognize the semantics of that name then the processor is required to skip (i.e., generate no tuples for) the entire XML element, including its content, whose name is unrecognized or that has an attribute whose name is unrecognized.]] -- http://www.w3.org/TR/REC-rdf-syntax/ section 6 Some test cases of how the proposed change would work Test Case 1 http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/att-0070/01-rdf-ns-prefix-confusion-2.rdf MUST return two statements (s,p,o form): (http://foo, rdf:type, http://example.org/Class) (http://foo, http://example.org/property, "bar") Test Case 2 http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/att-0070/02-rdf-ns-prefix-confusion-3.rdf MUST return the same two statements. I'm working on individual tests for each attribute on The List but I want confirmation it is the definitive list. Dave
Received on Thursday, 17 May 2001 11:38:18 UTC