W3C home > Mailing lists > Public > xmlschema-dev@w3.org > March 2011

Re: Classroom critique of XML Schema 1.1

From: Michael Kay <mike@saxonica.com>
Date: Sat, 19 Mar 2011 23:34:53 +0000
Message-ID: <4D853D9D.7030003@saxonica.com>
To: "Costello, Roger L." <costello@mitre.org>
CC: "xmlschema-dev@w3.org" <xmlschema-dev@w3.org>

> One student made the following remark after learning of the restrictions on<assert>  and<alternative>  and the inheritable attributes:
>     I see no reason for using XML Schema 1.1 since
>     I can do everything (and more) using the combination of
>     XML Schema 1.0 and Schematron. Plus, with
>     Schematron I get friendly, user-defined
>     diagnostic messages, which I don't get from
>     either XML Schema 1.0 or 1.1
> How would you respond to that? What does XML Schema 1.1 give that can't already be obtained using XML Schema 1.0 and Schematron?

You simply have to look at all the messages that ask "How do I write a 
schema to do X?" and the answers that say "In XSD 1.0 you can't, but in 
XSD 1.1 you can do it like this:...". That's your answer.

Of course XSD 1.1 assertions don't give you any validation capability 
that can't already be achieved using XSD 1.0 + Schematron, or XSD 1.0 + 
XSLT, or XSD 1.0 + Java. But (a) no-one wants to use two technologies if 
one will do, and (b) XSD is not only about validation.

Michael Kay
Received on Saturday, 19 March 2011 23:35:24 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 7 January 2015 14:56:19 UTC