FW: use of the XML Schema & DTD to formalize specs

Forwarding our discussion to the WG list. Will forward Dimitris's answer

-----Original Message-----
From: Kirill Gavrylyuk 
Sent: Thursday, April 18, 2002 9:11 AM
To: 'Dimitris Dimitriadis'
Subject: RE: Telcin discussion items

For the 2. - this is not done yet, but would be a useful feature. If we
have a standard schema for xml versions of all the specs that reflects
the spec guidelines requirements (having elements for assertions with
unique ID, elements for sections, paragraphs and Conformance clause),
extracting testable assertions and binding testsuites to the specs would
be easier.

For 1, here are the facts:
The scope of XML Schema (and DTD) is lexical validation. They are not
even type systems strictly speaking. You can not describe semantic
constraints using schema or DTD. WGs like XML Protocol, XML Schema, Web
Services Design Language, XQuery use schema to describe the types of
language constructions. But not the behavior. Not every XML language can
be described with XSD or any other schema either. Take XSLT for example.

Formalizing specifications
There are number of efforts in direction of formalizing specifications,
in order to automate analysis, generate testcases. No need to invent
anything new. You can look at the recent work on model based testing,
Abstract State Machine Language [1] for example. I'm sure there are a
lot of other projects in this direction. 

The benefit of using ASML or other techniques to formalize specification
is that 
- you can compile and execute the spec and verify for conflicts, vague
areas and unintended behaviors. 
- you can automatically generate models and test cases from them. I saw
it working in real projects. 

The drawback is that 
- this task is heavy, sometimes harder then to create an actual
- the formalized spec is less human-readable then XML Schema 
- you cannot do this without having an initial spec written in english.

The bottom line - providing list of testable assertions as an addendum
to the english version of the spec is the best WG's bet from the
cost/benefit point of view. Leave the rest to vendors, since they have
to create specs for their products based on the W3C spec too.

[1] http://research.microsoft.com/foundations/asml/  

-----Original Message-----
From: Dimitris Dimitriadis [mailto:dimitris@ontologicon.com] 
Sent: Thursday, April 18, 2002 5:54 AM
To: Kirill Gavrylyuk
Subject: Re: Telcin discussion items

I want to investigate 1. Why is it not possible to use a schema to write

a specification?

I take 2 to be trivially true, at least in so far as the specifications 
are valid XHMTL.


On Thursday, April 18, 2002, at 02:16 , Kirill Gavrylyuk wrote:

> Hi, Dimitris!
> Wanted to double check  - is your intent to
> 1. use schemas as language to write specifications or
> 2. to use the same schema for the XHTML version of all the W3C specs.
> I agree with 2, I'm opposed to 1 since it's not possible.
> -----Original Message-----
> From: Dimitris Dimitriadis [mailto:dimitris@ontologicon.com]
> Sent: Wednesday, April 17, 2002 3:50 PM
> To: www-qa-wg@w3.org
> Subject: Telcin discussion items
> QA WG,
> below please find the items for discussion I propose for my part of
> the introduction to the Specification guidelines document:
> 1. motivation for using advanced schemata for specificaiton authoring
> 2. benefits (better control over information extraction, normative 
> specification generation as well as automated test assertions) 3. Look

> at what is being done in Wg's 4. Rules for spec authoring similar to 
> pub rules that exist today
> I hope to have discussion on:
> 1. added effort on behalf of WG's
> 2. how to generate the normative schema(ta) to use when authoring a
> specification 3. generalized framework for generating normative (html)

> versions of specifications
> /Dimitris

Received on Thursday, 18 April 2002 13:26:11 UTC