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RE: Principle of Least Power

From: Bullard, Claude L \(Len\) <len.bullard@intergraph.com>
Date: Wed, 8 Feb 2006 14:31:42 -0600
Message-ID: <15725CF6AFE2F34DB8A5B4770B7334EE0BB1FE49@hq1.ingr-corp.com>
To: "Dan Connolly" <connolly@w3.org>
Cc: "Elliotte Harold" <elharo@metalab.unc.edu>, "Henry S. Thompson" <ht@inf.ed.ac.uk>, <noah_mendelsohn@us.ibm.com>, <Vincent.Quint@inrialpes.fr>, <www-tag@w3.org>

True and thanks.  It takes the schemas as a test case to 
apply the principle and tests the metrics.  I think that 
is useful because a lot of people in the know were around 
for those debates.  This can improve our thinking even if 
it outs some fog from the past.

len

From: www-tag-request@w3.org [mailto:www-tag-request@w3.org]

> For example, the Microsoft submission for xsd was 
> quite a bit less powerful but the W3C selected xsd.  Did the W3C 
> violate the principle or is the principle not a design criteria?

Interesting question.

We didn't do a requirements document... er... oops... yes,
we did! I just forgot about it: http://www.w3.org/TR/NOTE-xml-schema-req
  http://www.w3.org/TR/1999/NOTE-xml-schema-req-19990215

I think we might have done well to discuss this requirement more
and refine it:

"inheritance: Existing mechanisms use content models to specify part-of
relations. But they only specify kind-of relations implicitly or
informally. Making kind-of relations explicit would make both
understanding and maintenance easier"

It doesn't seem testable, as stated. And I'm not sure it clearly
states a requirement that the ultimate XSD design meets that the
earlier submissions did not meet.

It also would have been good to explicitly decide on and publish
the requirements that separte XSD from relax-NG. As I recall,
they relate to knowing types early or something, and the use
cases have to do with databinding. I know the community has discussed
them at length, and it would have been nice to have that
discussion reflected in the requirements document.

Hmm... this question is much more "close to home" than some
of the more academic topics. It might be worth adding it
as an example in the finding. It would take quite a bit of
research to establish the relevant facts, and it might
involve some post-hoc judgement calls. Hmm.
Received on Wednesday, 8 February 2006 20:31:59 GMT

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