Re: [xmlIDsemantics-32] new draft finding

At 07:24 2003 10 05 +0200, Chris Lilley wrote:

>Hello www-tag,
>
>I have updated the draft finding "How should the problem of
>identifying ID semantics in XML languages be addressed in the absence
>of a DTD?"
>http://www.w3.org/2001/tag/doc/xmlIDsemantics-32.html


In various places before section 7 you seem to suggest that one
can get ID typing equally from DTDs and XML Schemas.  It's not 
until the fourth paragraph of section 7 that you note "[t]he fact 
that a type ID declared in a DTD is not exactly equivalent to a 
type ID declared in a W3C XML Schema...."

It might be useful to expand on this point a bit more.  The
difference at the infoset level is that DTD processing causes
the [attribute type] infoset property to be set to ID whereas
XML Schema processing sets the type to xs:ID via the [type 
definition] family of PSVI properties.

If some processor that currently consumes infosets (perhaps via
SAX events or some other API) only looks at the [attribute type] 
infoset property to determine IDness (as it quite likely the case
in many currently existing processors), then conflating the "IDness" 
conferred by a DTD and that conferred by XML Schema is misleading.
This difference adds an important disadvantage to the XML Schema 
solution in my opinion:  it would not automatically work with existing 
tools that assume IDness is determined solely by the [attribute type] 
infoset property (or equivalent) and would therefore increase the
adoption overhead.

paul