[Note to potentially frightened newbies: this has little or nothing to
do with XML; rather, it's about what XML *isn't*, rather than what it
> I don't think PMC is possible in XML (someone prove me wrong :-)
I'll prove you right. Pernicious mixed content is when PCDATA is
permitted in some places in a content model but not others. Because
of SGML's weird rules, this means you suddenly have to get very
careful about where you allow otherwise innocuous whitespace.
The only way to have PCDATA in a content model in XML is governed by
production , "Mixed", in REC-XML; it allows
ONLY. No PMC.
[John E. Simpson]
> Production 's definition aside, I don't think I've *ever* heard
> (a) referred to as "mixed content." Maybe "PCDATA content"?
It's defined in production  of ISO 8879:1986; it is the kind of
content that allows data characters. It *can* have elements, but if
it doesn't, it's still mixed.
 Coined, I believe, by Terry Allen.
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