XSV Version 1.3

Date:      28 Oct 2001 18:40:46 +0000
From:      "Henry S. Thompson" <ht@cogsci.ed.ac.uk>
To:        xmlschema-dev@w3.org
Subject:   New release of XSV: significant change

Both the web [1] and the download [2] implementations of XSV have been upgraded to XSV 1.3, which represents a significant change in XSV internals.

Hitherto, XSV has pre-validated all schema documents involved in a schema-validation episode with the DTD for schemas. This was both not quite right, in that it meant certain constraints were not enforced, because not expressed in the DTD, and messy, in that if a schema document included an internal subset, it was tricky to preserve it.

With the advent of version 1.3, all schema documents are now pre-validated with a pre-compiled version of the schema for schemas itself. Even if a DOCTYPE is present, XML 1.0 validation will not be performed, although processing will reflect attribute defaults and general entity bindings, as required by XML 1.0.

I've done my best with regression testing etc. to ensure that this new release is working properly, but such a major change is bound to introduce new vulnerabilities -- early feedback about crashes and bugs will be welcome.

[1] http://www.w3.org/2001/03/webdata/xsv
[2] ftp://ftp.cogsci.ed.ac.uk/pub/XSV/XSV13.EXE

Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
          W3C Fellow 1999--2001, part-time member of W3C Team
     2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
            Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk
                     URL: http://www.ltg.ed.ac.uk/~ht/

Prepared by Robin Cover for The XML Cover Pages archive. For schema description and references, see "XML Schemas."

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