[DFDL-WG] Action 242 - valueLength and contentLength function wording

[Steve Hanson]

Mike

23.5.3.1. Value length is only a function of the dfdl:encoding property if 
the element has a text representation. Not sure this needs to be 
(re)stated here.

23.5.3.1. "The value length is computed from the DFDL infoset value, 
ignoring the dfdl:length or dfdl:textOutputMinLength property. Other DFDL 
properties which affect the length of a text or binary representation are 
respected, it is only an explicit length which is ignored." Last sentence 
is too imprecise - should be phrased in terms of the grammar. 

23.5.3.1. "If the second argument is 'characters' then the element must 
have text representation and it is a schema definition error otherwise". 
Yes but only for a simple type, so should be qualified.

23.5.3.1. "If the second argument, giving the length units, is 
'characters', then recursively, this complex type element must have text 
representation throughout all its contained elements and framing, all of 
which must also use a uniform character set encoding."  I can't see that 
restriction elsewhere in the spec when it talks about length of 
ComplexContent and lengthUnits 'characters' - I was expecting it to be in 
section 12.3.4 or 12.3.7.3 which face the same issue - but it isn't. Did 
we decide not to have this restriction? Without such a restriction, how 
does the unparser come up with a meaningful length (unless it re-parses)? 
(Tim - what does IBM DFDL do here?)  What about delimiters and padding of 
children that use %#r entities? 

23.5.3.2. The points in 23.5.3.1 about escape characters, length as a 
function of encoding, and bottom up for complex elements, apply equally to 
23.5.3.2.  It might be easier just to say in 23.5.3.2 that 
dfdl:contentLength for complex elements is same as dfdl:valueLength, and 
for simple elements differs only by the additional inclusion of 
LeftPadding and RightPadOrFill regions.

Also noted in passing:

Specified length - An item has specified length when dfdl:lengthKind is 
"implicit", "explicit", or "prefixed". 

should be 

Specified length - An element has specified length when dfdl:lengthKind is 
"implicit" (simple type only), "explicit", or "prefixed".  

Regards
 
Steve Hanson
Architect, IBM DFDL
Co-Chair, OGF DFDL Working Group
IBM SWG, Hursley, UK
smh at uk.ibm.com
tel:+44-1962-815848



From:   Mike Beckerle <mbeckerle.dfdl at gmail.com>
To:     "dfdl-wg at ogf.org" <dfdl-wg at ogf.org>, 
Date:   20/03/2014 17:21
Subject:        [DFDL-WG] Action 242 - valueLength and contentLength 
function        wording
Sent by:        dfdl-wg-bounces at ogf.org



See attached doc which is proposed revisions to section 23.5.3

Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | 
www.tresys.com
Please note: Contributions to the DFDL Workgroup's email discussions are 
subject to the OGF Intellectual Property Policy
--
  dfdl-wg mailing list
  dfdl-wg at ogf.org
  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/20140324/a7939f1b/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Action-252-DFDL-Functions-23.5.3.docx
Type: application/octet-stream
Size: 33938 bytes
Desc: not available
URL: <http://www.ogf.org/pipermail/dfdl-wg/attachments/20140324/a7939f1b/attachment-0001.obj>