- From: Felix Sasaki <fsasaki@w3.org>
- Date: Mon, 09 Jan 2006 16:56:00 +0900
- To: "Ian Hickson" <ian@hixie.ch>, "Bjoern Hoehrmann" <derhoermi@gmx.net>
- Cc: spec-prod@w3.org, www-qa@w3.org
+1 for the proposal of Bjoern to standardize the EBNF, and my many thanks as a co-author of http://www.w3.org/TR/2005/WD-its-20051122/ for pointing out that we need to define the EBNF format in that document. If you want to make that point as a comment on the working draft, please tell me or just send a mail to www-i18n-comments@w3.org Also an encouragement to use the EBNF. At least for specification whose semantics is very closely bounded to a context free grammar with a lot of non-terminals (like XPath, XQuery, XML itself, ...), the EBNF helps the reader and implementer a lot. Relying mainly on formal grammar was a main design principle of XML, see http://www.textuality.com/sgml-erb/dd-1996-0001.html (principle 8). Regards, Felix On Mon, 09 Jan 2006 16:05:01 +0900, Ian Hickson <ian@hixie.ch> wrote: > > On Mon, 9 Jan 2006, Bjoern Hoehrmann wrote: >> >> I think W3C should publish a Recommendation or a Group Note defining the >> EBNF format "defined" in http://www.w3.org/TR/REC-xml/#sec-notation and >> elsewhere. This is needed because the definition in the XML 1.0 >> Recommendation is incomplete and W3C technical reports define more and >> more variants of it for which it is not easy to tell whether they are >> different or not. > > An alternative would be for the W3C to standardise on ISO 14977:1996 or > RFC 2234. > > Personally I would discourage the use of BNF, however, as it makes it > very > difficult to define error handling rules, and specifications often forget > to define how to go from the parsed tree to the semantics that the > specification defines, leaving it up to UA implementors to work out the > implied mapping. > > For example, as far as I can tell, there is nothing in the XML 1.0 spec > that says what the syntax of an XML Declaration (as found in a prolog) > is. http://www.w3.org/TR/REC-xml/#NT-XMLDecl does not fulfill your needs? Regards, Felix. > One can make a guess, but the spec doesn't say whether we are right. The > reliance on EBNF has made it easier to leave the mapping of the strict > syntax definitions to the actual semantics to implication than to make > the > spec full and complete. >
Received on Monday, 9 January 2006 07:56:14 UTC