Bit fields issue.

I have been expecting bit fields to work like this:

<element name="threeBitField" type="xs:int" dfdl:length="3" dfdl:lengthUnitKind="bits"/>

That is, bit fields are representational, but not part of the type system.

Is this idea sufficient?

Alternatively we could add a dfdl:bit type, which is a subtype of xs:byte having values only 0 and 1. Then you could do things like this:

<element name="myBits" type="dfdl:bit" maxOccurs="3" minOccurs="3" dfdl:alignment="0"/>

I put the alignment tag on to emphasize that there's no padding between the bits.  



Mike Beckerle/Worcester/IBM@IBMUS
Sent by: owner-dfdl-wg@ggf.org

09/02/2005 04:34 PM

To
"Robert E. McGrath" <mcgrath@ncsa.uiuc.edu>
cc
dfdl-wg@gridforum.org, owner-dfdl-wg@ggf.org
Subject
split into multiple topics - Re: [dfdl-wg] Issues: additional data types






I'd like to split this topic into several distinct ones:

Arrays - I have a placeholder for this in the doc.

Opaque and "code" types are separate. This is related also to the concept of "open content".

Enums

Bitfields

Pointers


Mike Beckerle
Architect, Scalable Computing
IBM Software Group
Information Integration Solutions
Westborough, MA

"Robert E. McGrath" <mcgrath@ncsa.uiuc.edu>
Sent by: owner-dfdl-wg@ggf.org

09/02/2005 03:13 PM


To
dfdl-wg@gridforum.org
cc
Subject
[dfdl-wg] Issues: additional data types







Greetings,

Here is an "issue" for the DFDL: additional data types that should
be considered.

Please see attached.

---
Robert E. McGrath
National Center for Supercomputing Applications
University of Illinois, Urbana-Champaign
Champaign, Illinois 61820
(217)-333-6549

mcgrath@ncsa.uiuc.edu