Wellformedness

[Staffan Måhlén <staffan.mahlen@ausys.se>]

Several threads have lately been describing wellformedness as rock-solid. In
a message [1] last week i questioned a (very) minor point of the XML 1.0
second edition recommendation on this. I have now also tested using the W3C
validator but that one too complained, although i am not quite sure that not
using the -V option implies only checking wellformedness. The problem seems
to be that at least one major parser as well as the W3C validator is not
compliant regarding one minor wellformedness issue.

A few more direct questions could be:

Is the example wellformed?
Are internal DTDs mandatory to parse when only checking wellformedness?
Are internal entities required to be included if only checking
wellformedness?
(the entity table in the spec suggests the two above are true but there
might be some more vague fallback?)

Are there other wellformedness issues where commonly used parsers fail?
Do other parsers see my example as wellformed?
Should two-step parsing of internal DTDs be required (when not validating)?
Is event-based parsing (SAX) supposed to handle this (or does it already)? 
Why not make PE declarations mandatory (WFC) before usage?

With the last question probably being my main question. I wish to understand
the reason for the change. The "feature" is probably never used, but i
suspect there is something behind the errata i am missing. Are there grey
areas regarding wellformedness and the borderline between
validating/wellformed? Or am i just not reading the spec right?

/Staffan Måhlén

[1] http://lists.xml.org/archives/xml-dev/200103/msg00360.html 
...contained the Example:

<?xml version="1.0"?>
<!DOCTYPE test [
<!ELEMENT test (#PCDATA)>
%zz; 
<!ENTITY % zz '&#60;!ENTITY nonTricky "error-prone" >' >
]>
<test>
	&nonTricky;
</test>