[DFDL-WG] action 224: add section for implementation defined limits

Sat Oct 19 13:59:19 EDT 2013

All,

Attached are the first few implementation-specific features divided up between implementation-defined and implementation-dependent features.  Three are implementation-defined and two are implementation-dependent.

The intent is to add two definitions to the spec, similar to this snippet from the XProc specification (http://www.w3.org/TR/xproc/#conformance):

Conformant processors must implement all of the features described in this specification except those that are explicitly identified as optional.

Some aspects of processor behavior are not completely specified; those features are either implementation-dependent or implementation-defined.

[Definition: An implementation-dependent feature is one where the implementation has discretion in how it is performed. Implementations are not required to document or explain how implementation-dependent features are performed.]

[Definition: An implementation-defined feature is one where the implementation has discretion in how it is performed. Conformant implementations must document how implementation-defined features are performed.]

I'm still working through the spec; I thought I'd send these off now to begin discussion.

Fyi,

Jonathan

>-----Original Message-----

>From: Steve Hanson [mailto:smh at uk.ibm.com]

>Sent: Wednesday, September 18, 2013 3:30 AM

>To: Cranford, Jonathan W.

>Cc: dfdl-wg at ogf.org<mailto:dfdl-wg at ogf.org>; dfdl-wg-bounces at ogf.org<mailto:dfdl-wg-bounces at ogf.org>

>Subject: Re: [DFDL-WG] action 224: add section for implementation defined limits

>

>Jonathan

>

>Thanks for citing that example. I have added a summary to the minutes of

>yesterday's WG call.

>

>Please go ahead and trawl the document for implementation defined/dependent

>things.

>

>Please also raise a public comment to track, at

>http://redmine.ogf.org/projects/editor-pubcom/boards/15

><http://redmine.ogf.org/projects/editor-pubcom/boards/15> .

>

>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> <mailto:smh at uk.ibm.com>

>tel:+44-1962-815848

>

>

>

>From:        "Cranford, Jonathan W." <jcranford at mitre.org<mailto:jcranford at mitre.org>>

>To:        "dfdl-wg at ogf.org<mailto:dfdl-wg at ogf.org>" <dfdl-wg at ogf.org<mailto:dfdl-wg at ogf.org>>,

>Date:        17/09/2013 16:11

>Subject:        [DFDL-WG] action 224: add section for implementation defined limits

>Sent by:        dfdl-wg-bounces at ogf.org<mailto:dfdl-wg-bounces at ogf.org>

>

>________________________________

>

>

>

>

>All,

>

>Action item 224 was raised two weeks ago during the WG call.

>

>224 Add section for implementation defined limits (All)

>3/9: Several places in the spec cite this, should be grouped. Currently partially

>listed in section

>2.6.

>Also note distinction between 'implementation defined' and 'implementation

>dependent'. Check

>spec for correct usage.

>Resolve during public comment.

>

>The action item was created based on a comment I made during the call, so I

>thought it’d be good to provide an example of the distinction I was trying to

>make.

>

>The W3C XProc specification does a great job of differentiating between

>implementation-defined and implementation-dependent features, with a

>convenient list of each in the appendix.

>

>Appendix A (http://www.w3.org/TR/xproc/#conformance

><http://www.w3.org/TR/xproc/#conformance> ) contains the following text.

>Conformant processors must implement all of the features described in this

>specification except those that are explicitly identified as optional.

>Some aspects of processor behavior are not completely specified; those features

>are either implementation-dependent <http://www.w3.org/TR/xproc/#dt-

>implementation-dependent>  or implementation-defined

><http://www.w3.org/TR/xproc/#dt-implementation-defined> .

>[Definition: An implementation-dependent feature is one where the

>implementation has discretion in how it is performed. Implementations are not

>required to document or explain how implementation-dependent

><http://www.w3.org/TR/xproc/#dt-implementation-dependent>  features are

>performed.]

>[Definition: An implementation-defined feature is one where the implementation

>has discretion in how it is performed. Conformant implementations must

>document how implementation-defined <http://www.w3.org/TR/xproc/#dt-

>implementation-defined>  features are performed.]

>

>Section A.1 then lists all the implementation-defined features, and section A.2

>lists all the implementation-dependent features.

>

>I think the XProc spec provides a great example to follow on two counts.  First, it

>formally distinguishes between implementation-defined and implementation-

>dependent features.  The choice of terms isn’t nearly as important as the

>distinction itself, of course:  implementations must document how certain

>features are implemented.  In the DFDL realm, section 2.6 lists some

>implementation limits which always constitute schema definition errors; surely

>these are the types of details that must be documented by any DFDL

>implementation.  Using terminology such as “implementation-defined” and

>“implementation-dependent” would flag these types of documentation

>requirements for implementations within the specification.

>

>Second, all the implementation-defined and implementation-dependent features

>are listed in one place in the specification.  I think doing the same in the DFDL

>spec would provide a great resource for DFDL implementers.

>

>Comments?  If everyone agrees, I don’t mind taking the action to search through

>the document looking for candidates for inclusion in such a list.

>

>Sincerely,

>

>--

>Jonathan W. Cranford

>Senior Information Systems Engineer

>The MITRE Corporation (http://www.mitre.org <http://www.mitre.org/> )

> --

> dfdl-wg mailing list

> dfdl-wg at ogf.org<mailto:dfdl-wg at ogf.org>

> https://www.ogf.org/mailman/listinfo/dfdl-wg

><https://www.ogf.org/mailman/listinfo/dfdl-wg>

>

>Unless stated otherwise above:

>IBM United Kingdom Limited - Registered in England and Wales with number

>741598.

>Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.ogf.org/pipermail/dfdl-wg/attachments/20131019/f9eccfe2/attachment-0001.html>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: dfdl-implementation-defined.txt
URL: <http://www.ogf.org/pipermail/dfdl-wg/attachments/20131019/f9eccfe2/attachment-0001.txt>