RE: [dita] Feature Request: Make tgroup optional w/in table

["Grosso, Paul" <pgrosso@ptc.com>]

This isn't really an OASIS table issue.  It's a conref issue.

The problem arises whenever you conref to an element whose
content model doesn't allow it to be empty.  The problem is
just due to the basic definitions of XML and DITA's conref.
Basically, the design of DITA's conref is not completely
compatible with XML.

We could allow DITA's table element to be empty--and assume
this situation would only be used in the conref case--but if 
the table element is not empty, tgroup needs to be required.

paul 

> -----Original Message-----
> From: Don Day [mailto:dond@us.ibm.com] 
> Sent: Friday, 2007 March 02 22:27
> To: W. Eliot Kimber
> Cc: dita@lists.oasis-open.org
> Subject: Re: [dita] Feature Request: Make tgroup optional w/in table
> 
> The story seems related to the choice of the OASIS XML 
> Exchange Table Model
> as the definitive version for DITA.
> http://www.oasis-open.org/specs/tm9901.html
> 
> In that default DTD, the content model for table is effectively:
> 
> <!ENTITY % tbl.table-titles.mdl "%titles;,">
> <!ENTITY % tbl.table-main.mdl   "tgroup+">
> <!ENTITY % tbl.table.mdl        "%tbl.table-titles.mdl;
> %tbl.table-main.mdl;">
> ...
> <!ELEMENT %tbl.table.name; (%tbl.table.mdl;)>
> 
> In the DITA adaptation, the equivalent specialization-enabled 
> declaration
> is:
> 
> <!ENTITY % tbl.table-titles.mdl "((%title;)?, (%desc;)?)?,">
> <!ENTITY % tbl.table-main.mdl   "(%tgroup;)+">
> <!ENTITY % tbl.table.mdl        "%tbl.table-titles.mdl;
> %tbl.table-main.mdl;">
> ...
> <!ELEMENT %tbl.table.name; (%tbl.table.mdl;)>
> 
> Thus, tgroup effectively remains one or more by inheritance from the
> Exchange Table Model.  Due to the wide use of this model 
> across most XML
> DTDs that use tables, we are sort of faced with either 
> changing this design
> uniquely for DITA, or with pushing the Why question back to 
> the framers of
> the 1999 document.  With my DITA specialization hat on, I can see the
> rationale of your request. With my Chair hat on, I worry what 
> impact such
> change might have on editor implementations that may have 
> somehow built
> dependencies on the requiredness of tgroup (ensuring that new 
> tables get a
> default setup when created, perhaps) in which the relaxation 
> might affect
> how usability is perceived.
>                                                               
>              
>              "W. Eliot Kimber"                                
>              <ekimber@innodata-isogen.com>

>           To  <dita@lists.oasis-open.org>         
>              03/02/2007 02:48  
>                                                               
>      Subject: [dita] Feature Request: Make tgroup 
>                optional w/in table    
>              
> I am creating documents from legacy where all the tables are 
> being used by reference.
> 
> Because tgroup is required w/in table, it means that all my 
> conrefs look like this:
> 
> <table conref="tables_205-15-60.xml#table-001">
>    <tgroup cols="1">
>      <tbody>
>        <row>
>          <entry></entry>
>        </row>
>      </tbody>
>    </tgroup>
> </table>
> 
> Which seems a little silly.