Re: C.4 Undeclared entities?

[Charles Goldfarb:]

| >A well-formed XML document without a DTD describes a logical tree of
| >arbitrary depth.  HTML does not, unless you overload the DIV tag in
| >ways that are horrible to contemplate.  This is a difference.
| But not enough to win out against "HTML with user extensions via style
| sheet".  To teach the value of "a logical tree of arbitrary depth" we
| need to teach the value of structure and document types.

There is a difference between the concept of structure and the concept
of document types.  They are both valuable concepts, but they are not
joined at the liver.

| This case is weakened significantly if we don't require DTDs and offer
| the possibility of validation of all XML documents.

There is a difference between requiring DTDs and making it possible to
validate XML documents.

| We needn't (shouldn't) require validation at rendition time, but there
| should always be a DTD that can be accessed for editing and/or
| validation. Without it, XML won't be a sufficient improvement on HTML
| to win a significant market.

Based on my experience with the HTML market and the applications that
HTML will soon be called upon to support, I disagree.