Re: [xml-dev] Wikipedia on XML

[Elliotte Rusty Harold <elharo@ibiblio.org>]

On Fri, Aug 21, 2009 at 7:46 PM, Liam Quin<liam@w3.org> wrote:

> As for (per ERH) the DTD modifying the infoset, strictly speaking
> the XML infoset specification gives us a way to describe the
> result of parsing an XML document, and since DTD processing happens
> as part of that process, there's no modification... although
> maybe I'm being overly pedantic, as it's certainly true you can
> end up with different results if you parse the same XML docuent but
> with or without its DTD.  Just as you can if you use or don't use
> a W3C XML Schema (XSD) thta supplies default content, for example.

We don't have to speak in infoset language here. The critical points are:

1. All conformant parsers MUST process the internal DTD subset.
2. The DTD, including the internal DTD subset, can define new entity
references. If they're defined in the internal DTD subset, the parser
must expand these.
3. Nothing except a DTD can define entity references.

There are other details (default attribute values, malformed internal
DTD subsets, external entity references) but those are what really
make it impossible to just ignore DTDs or claim they're just one kind
of schema language.

-- 
Elliotte Rusty Harold
elharo@ibiblio.org