- From: Joseph M. Reagle Jr. <reagle@w3.org>
- Date: Fri, 11 May 2001 10:19:43 -0400
- To: xml-editor@w3.org
[DanC recommended I also send this question to xml-editor for a answer to the question, though CG may still need to take some action.] A question was recently raised with respect to Canonical XML specification's use of "DTD" to refer to both "document type declaration" and "document type definition". http://www.w3.org/TR/2001/REC-xml-c14n-20010315 [Harold] believes this is in error and not supported in his interpretation of the XML1.0 (2nd) spec; [Boyer] believes this usage is in keeping with his interpretation of XML1.0 (2nd), and is also found in XPath. (I share Harold's interpretation of the XML 1.0 spec (and don't infer the same thing Boyer does from XPath)) Regardless, in either case, we realize this is a minor issue (i.e., it doesn't substantively affect implementations), but if we've made a mistake, it's likely to be made by others and we don't want to encourage them by allowing citations to Canonical XML on that point. So, I'm requesting the CG instantiate guidance on the interpretation (from the CG or relevant WG) and provide a recommendation on which specs (perhaps only Canonical XML, if any) should issue an erratum on this point? (See [3] for Boyer and Harold agreeing the XML spec can lead to this confusion.) [Harold ] http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/2001AprJun/0100.html >... The document type declaration and document type definition are two >different things and need two different abbreviations. "Document type >declaration" can be abbreviated "DOCTYPE declaration" if necessary. It >cannot be abbreviated DTD. > >The only truly normative spec on this point is XML 1.0. In the 2nd edition >section 2.8 clearly states: > >[Definition: The XML document type declaration contains or points to markup >declarations that provide a grammar for a class of documents. This grammar >is known as a document type definition, or DTD. The document type >declaration can point to an external subset (a special kind of external >entity) containing markup declarations, or can contain the markup >declarations directly in an internal subset, or can do both. The DTD for a >document consists of both subsets taken together.] > >This normative part of the spec clearly indicates that "DTD" means >"document type definition" and is distinguished from "document type >declaration" [Boyer] http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/2001AprJun/0101.html >I currently believe that DTD is used >interchangeably as an abbreviation for both the document type definition >grammar and the document type declaration. Note, however, that I take >my understanding of what DTD means directly from its usage in the XML >Recommendation [1], which incidentally seems to use DTD more often to >refer to the DTDeclaration. Moreover, the same usage for DTD appears in >XPath [2]. http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/2001AprJun/att-0104/00-part >You cannot introduce a document type 'definition' into an XML document >without a DOCTYPE, and you cannot have a DOCTYPE which does not introduce a >document type 'definition'. The XML 1.0 spec refers to the production 28 >as the Document Type Definition, then proceeds to define the doctypedecl >non-terminal. And, based on who reads the so-called definition, there >seems to be nothing wrong with this. Moreover, all of the things inside of >a document type 'definition' are all referred to as 'declarations'. [3] http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/2001AprJun/0103.html > >To wit, immediately below the > >definition you cited, there appears the following: > > > >Document Type Definition > > > >[28] doctypedecl ::= '<!DOCTYPE' S Name (S ExternalID)? S? ('[' > >(markupdecl | DeclSep)* ']' S?)? '>' [VC: Root Element Type] > > > >In other words, a document type definition is defined to be that which > >gramatically resolves to a document type declaration. > > > >I agree that's confusing and I should probably file an request for >clarification on that as well. However, that heading is NOT the >normative definition of a document type definition or DTD. The >normative definition is given in the Definition paragraph quoted >above. __ Joseph Reagle Jr. http://www.w3.org/People/Reagle/ W3C Policy Analyst mailto:reagle@w3.org IETF/W3C XML-Signature Co-Chair http://www.w3.org/Signature W3C XML Encryption Chair http://www.w3.org/Encryption/2001/
Received on Friday, 11 May 2001 10:19:55 UTC