SAX: Next Round (Lexical Event Handler)

John Cowan cowan at locke.ccil.org
Mon Feb 1 15:24:44 GMT 1999


David Megginson scripsit:

> Do we need the declarations, or just the boundaries -- or, in other
> words, do we need to provide information about declared but unused
> external parsed entities?  Sorry I'm too lazy to puzzle this out from
> the spec right now.

The DOM is silent on the matter of completeness in general.  In this
case we are told that Entity objects model entities, not ENTITY
declarations, so presumably a declared but unused entity would not
be modeled.

>  >      *  expose values of defaults so that the DOM can ensure
>  >         that defaulted attributes always have values;
> 
> The parser should take care of this.
> 
>  >      *  distinguish attributes which were defaulted from those
>  >         that were explicitly in the document.
> 
> Yes, this is necessary, as a few others have also pointed out
> (grumble, grumble).

Unfortunately these items go together for DOM purposes, something
I hadn't noted before.  If the application removes an attribute
that has a default but didn't use it, it is magically reinserted with
the default value.  So DOM builders need both the default and the
actual value.  (This also affects you-know-what.)
 
> Probably -- the problem is that if we extend Parser then we'll have
> both a setDocumentHandler and a setLexicalDocumentHandler event, and
> that causes some funny problems that I'd rather punt.

Not necessarily.  setDocumentHandler could simply check if its
argument is an instanceof LexicalDocumentHandler, thus making
setLexicalDocumentHandler unnecessary.
 
-- 
John Cowan	http://www.ccil.org/~cowan		cowan at ccil.org
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at ic.ac.uk
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/
To (un)subscribe, mailto:majordomo at ic.ac.uk the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at ic.ac.uk the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at ic.ac.uk)




More information about the Xml-dev mailing list