[DFDL-WG] could you clarify statement made on the call today

[Cranford, Jonathan W.]

Steve,

Excellent - thanks for the clarification.  That puts a lot of things into perspective for me.

And thanks for the pointer to the XDM mapping document.  I was just looking at XDM for inspiration yesterday, so the timing couldn't be better.

Have a good vacation,

Jonathan

>-----Original Message-----
>From: Steve Hanson [mailto:smh at uk.ibm.com]
>Sent: Wednesday, July 24, 2013 5:24 AM
>To: Cranford, Jonathan W.
>Cc: dfdl-wg at ogf.org
>Subject: Re: could you clarify statement made on the call today
>
>Jonathan
>
>Yes that's the principle, but it goes further than that. The DFDL infoset is typed,
>whereas the XML infoset isn't. The results of parsing a DFDL-described document
>and then applying DFDL validation to the resultant DFDL infoset is the same as
>parsing the equivalent XML document and applying XML Schema 1.0 validation,
>where 'results' means 'the validation errors that are detected'.
>
>This principle has guided the WG in the design of several features. To hide
>elements from the DFDL infoset requires the use of a 'hidden group' - simply
>doing the obvious thing and adding a dfdl:hidden property to an element would
>break the principle. To get an assert to fail without throwing a processing error
>meant inventing recoverable errors - re-using validation errors would break the
>principle.
>
>For you inspection and sanitization capability, I would recommend looking at
>XDM, the model used by XPath 2.0, XSLT 2.0 and XQuery. I think this is the natural
>higher-level model to adopt for a common DFDL and XML framework. I created
>this OGF document to describe how to map DFDL infoset to/from XDM.
>http://redmine.ogf.org/dmsf_files/8111?download=
><http://redmine.ogf.org/dmsf_files/8111?download=> .
>
>Regards
>
>Steve Hanson
>Architect, IBM Data Format Description Language (DFDL)
>Co-Chair, OGF DFDL Working Group <http://www.ogf.org/dfdl/>
>IBM SWG, Hursley, UK
>smh at uk.ibm.com <mailto:smh at uk.ibm.com>
>tel:+44-1962-815848
>
>
>
>From:        "Cranford, Jonathan W." <jcranford at mitre.org>
>To:        Steve Hanson/UK/IBM at IBMGB,
>Cc:        "dfdl-wg at ogf.org" <dfdl-wg at ogf.org>
>Date:        23/07/2013 18:23
>Subject:        could you clarify statement made on the call today
>
>________________________________
>
>
>
>
>Steve,
>
>Could you clarify a statement made during today's DFDL WG call?
>
>I didn't quite catch the whole statement, but it sounded like you were saying a
>design goal of the WG was that the result of parsing a binary format using DFDL
>would result in a DFDL infoset roughly equivalent to the XML infoset obtained by
>parsing the same data in an XML format.  I don't think I quite captured that
>correctly, but it sounds like an important point, and I'd like to understand it
>further.
>
>For context, I've been asked to look at building an inspection and sanitization
>capability on top of DFDL, so I'm weighing the differences between DFDL Infoset
>and XML Infoset at the moment, and your comparison caught my attention.
>
>Thanks in advance,
>
>--
>Jonathan W. Cranford
>Senior Information Systems Engineer
>The MITRE Corporation (http://www.mitre.org <http://www.mitre.org/> )
>
>
>
>
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