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Re: RE: James Clark: XML versus the Web

• From: Jonathan Robie <jonathan.robie@redhat.com>
• To: xml-dev@lists.xml.org
• Date: Fri, 17 Dec 2010 14:13:37 -0500

On 11/30/2010 10:07 PM, Kurt Cagle wrote:

> Significantly, if you look at the most important "standards" in the
> W3C canon, the ones that had the biggest staying power usually were
> produced by one person and then "smoothed out". XPath (James Clark),
> XSLT 1 (James Clark) and 2 (Michael Kay) falls into that category, as
> does RNG (James Clark again), Schematron (Rick Jelliffe), XProc (Norm
> Walsh), XForms (Mark Birbeck and Micah Dubinko), XQuery (Michael
> Kay), RDFa (Michael Birbeck) and the like.

I do think you're right about XSLT 1 and 2. XPath has a more complex
history than you might think, involving more people than you might 
think. XQuery is a mongrel language, as its introduction points out:

http://www.w3.org/TR/xquery/

> XQuery is derived from an XML query language called Quilt [Quilt],
> which in turn borrowed features from several other languages,
> including XPath 1.0 [XPath 1.0], XQL [XQL], XML-QL [XML-QL], SQL
> [SQL], and OQL [ODMG].

XQuery started with a broad set of use cases, which were largely created 
by authors of the languages listed above. That turned into the XQuery 
Use Cases document, which originally did not include the queries, just 
the input and output.

We then put our heads down and tried to find a language that could do 
all the things we wanted it to, stealing liberally from existing 
languages, but changing the syntax to fit into one language. The first 
version of this, Quilt, satisfied the use cases but had a lot of issues 
that had to be ironed out in committee.

Quilt was designed by three people, in about 6 months. XQuery was 
refined by many more, over many years. I really think XQuery 1.0 is a 
significant improvement over Quilt.

On 12/01/2010 04:17 AM, Michael Kay wrote:

 > A correction here - my contribution to XQuery was entirely as part of
 > the "smoothing out" effort - my role was as bug-fixer. The original
 > ideas can be largely attributed to Jonathan Robie, Don Chamberlin,
 > and Dana Florescu.

Mike Kay's contribution has been huge, but it came after the bulk of the 
language was originally designed. Getting the details right has been 
extremely important.

XQuery continues to grow as a mongrel language, including new features 
like windowing and higher order functions that were not at all in the 
original design.

 > XQuery was very much a committee effort. The main reason it took
 > so long was that there were too many good people with creative ideas
 > participating in the process. That the final result had some
 > technical coherence can be largely attributed, in my view, to the
 > arbitration skills of Don Chamberlin, Mary Fernandez, and Paul Cotton.

I agree.

Jonathan