Re: Make DTDs optional?
On Sat, 28 Sep 1996 10:25:19 -0400, Paul Prescod
>But aren't DTDs integral to structural markup?
>My reading of Annex A.3 indicates that DTDs were primarily intended to be
>used for markup minimization. Goldfarb says: "Document type definitions have
>uses in addition to markup minimization." (a slight understatment =) )
Don't confuse the presentation order I chose for pedagogical reasons with the
order of importance for the uses of a DTD.
That paper was originally published in 1981, when data bases were in their
infancy and Don Knuth hadn't yet made text processing a legitimate subject for
computer science. (In fact, when I prepared it for the standard I had to do a
global change from GML to SGML; see footnote 9.) In that environment, it was
easier to explain a DTD by showing some easily grasped concrete uses of the
information that it contains. Tag omission is an especially good example for
this purpose because it emphasizes the distinction between tags and elements.
There are good reasons for XML to work without a DTD (at least for browsing and
other read-only applications), but the structure of my paper isn't one of them.
Charles F. Goldfarb * Information Management Consulting * +1(408)867-5553
13075 Paramount Drive * Saratoga CA 95070 * USA
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