- From: Michael Kay <mike@saxonica.com>
- Date: Mon, 27 Jun 2005 22:43:20 +0100
- To: "'Steven Ericsson-Zenith'" <steven@semeiosis.com>, <www-xml-schema-comments@w3.org>, <xmlschema-dev@w3.org>
> I want to add that since I wrote the note below I have read > the formal specification and my feeling about that document > is that it does more harm than good - especially since the > committee made it clear at the workshop that the document is > not considered a valid account of the standard. This is all > the more concern since I heard XPath and XQuery made use of > the spec. The XQuery and XPath specifications do not make any reference (either normative or informative, or even as background reading) to the formal specification that you mention. Some of the members of the XQuery WG may well have read it and used it to educate themselves, but that doesn't create a dependency. > > I guess I am puzzled as to why the committee did not follow > the precedent set by the XML standard and wonder what the > W3C broad position is - surely a recomendation regarding > formal specification for all the standards is appropriate. > A common mathematical basis and algebra in the standards > would seem useful to me. Working Groups are staffed by people with their own ideas, experience, and skills, and a directive of this kind that didn't match the needs of the particular WG and the skills of its members would achieve nothing. I have to say that my own experience of formal specifications (both inside and outside W3C) is that they invariably lag behind the informal specification by months, and in most cases are never completed. They also contain more bugs than the informal specification, because there are very few people with the time and the skills to read the specifications and spot the errors. In the case of the XQuery formal specification, there are a few external reviewers (for example, from universities) reporting bugs in the formal specification, but they tend not to be interested in the messier parts of the XML world (stuff like namespaces, whitespace, and relative URIs) which is where the bugs tend to hide. The people writing the formal specification have discovered bugs in the informal spec while writing the formal version, so the exercise has been worthwhile, but it's left us with the problem of two specs that are almost certainly inconsistent with each other. My own preference when writing specs is for "formal English". Writing a backwards-E rather than "there exists" does not make the spec any more precise or less ambiguous, it just makes it accessible to a smaller readership. Michael Kay http://www.saxonica.com/
Received on Monday, 27 June 2005 21:43:38 UTC