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Re: the need for document type name (was: Define a root in a DTD)
- From: "Christopher R. Maden" <crism@maden.org>
- To: xml-dev@lists.xml.org
- Date: Sun, 01 Jul 2001 13:24:55 -0700
At 07:01 1-07-2001, K. Ari Krupnikov wrote:
>What is the need for specifying the document element in an XML document
>declaration? It is my understanding that in SGML elements may be
>omitted, so if the outermost element might be <BODY> but
>
><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
>"http://www.w3.org/TR/html4/strict.dtd">
>
>tells the processor that HTML is the document element, and that <HTML>,
><HEAD>, <TITLE>, etc. are implicitly present.
>
>In XML, elements cannot be omitted, so looking at the document element
>should be sufficient. So is the requirement for a document declaration
>name simply for compatibility with SGML, or is there another reason?
You're absolutely right that it's redundant. It's mostly for
compatibility; that token in the DOCTYPE is required by SGML, so XML
couldn't just throw it out. It is also used by some editing tools to know
where in the DTD to start, so it's useful that way. And you can omit the
DOCTYPE altogether; it's only if it's present that the redundant root
element identification must be present.
-Chris
--
Christopher R. Maden, XML Consultant
DTDs/schemas - conversion - ebooks - publishing - Web - B2B - training
<URL: http://crism.maden.org/consulting/ >
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