RE: [dita] Repeated conrefs

This 
message has been in my drafts folder forever. Sorry. You'll have to read from 
the bottom to get context.

 

  
I do not think that your first 
  answer is consistent with the DITA spec. When NOT using conref, IDs for topic content 
  must be unique within the topic. My question was about conref’ing the same topic content element into the same 
  topic twice. I believe that this should be disallowed or a mechanism should be 
  provided for overriding the ID attribute.
  
The question about conref-fing topics twice was not 
  intended to be an implementation question: If it is disallowed then the DITA 
  specification should be explicit about that. 
  But why would conreffing an element twice be allowed but a topic twice is 
  disallowed?
  
If DITA disallows recursive conrefs then shouldn’t the DITA spec says 
  so? 

 

I’m therefore proposing 
three changes to the DITA specification. 

 

From: Michael 
Priestley [mailto:] 
Sent: Tuesday, October 11, 2005 3:36 
AM
To: Paul Prescod
Cc: 
Subject: Re: [dita] Repeated 
conrefs

 

Comments below... 

Michael Priestley
IBM DITA 
Architect
SWG Classification Schema PDT 
Lead
 

"Paul Prescod" 
<> wrote on 10/06/2005 07:50:36 
AM:

> By definition, every element that is conrefed has an 
“id” attribute.
> Is it therefore 
invalid to conref the same element into the same 
> topic twice? 

It is still valid. The 
id on most elements is not constrained to be unique, precisely to allow this as 
a valid case. 

>And to conref the same topic into a 
parent topic twice? 

This is not so valid. Topic-level elements 
must have unique ids. If the same topic gets conref'd into a document in 
multiple places, this does produce an error once the resolved document is 
parsed, and the conref processor doesn't currently check for 
that. 

> Is it legal for an element with a DITA conref to 
reference another 
> element with a conref? If so, shouldn’t DITA disallow 
mutually 
> recursive 
conrefs? 

It should, it's just an edge case that is 
expensive to check for, so I don't know of any process that currently does. 

>   
> And as an 
implementation question: how many validating conref 
> processors are known to exist and to support DITA semantics 
> (including specialization, ID, filtering) 
explicitly? 

The DITA Open Toolkit contains a 
specialization-aware domain-checking conref transform. I believe filtering is 
done in a separate step. 

>   

> 
 Paul Prescod 
>