Parameter Entity Reference Considered Harmful

Trevor Jenkins tfj at
Wed Sep 3 18:43:21 BST 1997

In making one more pass through the official grammar for XML, before 
I despatch my alternative version to the 5 people who've requested 
copies, I spotted a real dumb error in the doctype declaration.

The existing definition says:

doctypedecl ::= '<!DOCTYPE' S  Name (S
                ExternalID)? S? ('['
                %markupdecl* ']'  S?)? '>'

Now the notational devie of prefixing a production name with %, and
I quote, "specifies that <i>in the external DTD subset</i>..."
(emphasis copied from the definition). But notice that this
%markupdecl is NOT in the external DTD subset at all! Also the
definition of the % device introduces another set of ambiguities
from white space.

Me thinks that the existing official grammar is in desparate need of 
a re-write.

Regards, Trevor.


"Real Men don't Read Instruction Manuals"
   Tim Allen, Home Improvement

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