[Home] [By Thread] [By Date] [Recent Entries]

  • From: "Frank Boumphrey" <bckman@i...>
  • To: "David Megginson" <david@m...>, "xml-dev" <xml-dev@i...>
  • Date: Sat, 8 Jan 2000 23:19:00 -0500

> Wrong.  A document type needs to conform to the specification that
> defines it: the specification

Of course David is quite right! I should have said that a document must
conform to a schema, and that a schema can be a DTD, or a 'schema' or a
narative description, etc. ...

Frank
----- Original Message -----
From: David Megginson <david@m...>
To: xml-dev <xml-dev@i...>
Sent: Saturday, January 08, 2000 9:37 AM
Subject: Re: Well-formed and valid


> "Frank Boumphrey" <bckman@i...> writes:
>
> > > james anderson <James.Anderson@m...> writes:
> > >
> > > > > ... it is possible to have a document that is well-formed but
> > > > > not valid XML 1.0, but still conforms to Namespaces, RDF, or XLink
> > > > > (though not XHTML, which requires validity for strict
conformance).
> >
> > Well XHTML is no different from any other _document type_.  A document
type
> > such as docbook or XHTML must conform to a DTD or it would not be a
document
> > type!
>
> Wrong.  A document type needs to conform to the specification that
> defines it: the specification may or may not include a DTD, and may or
> may not require the DTD to be used, but the DTD is at best an optional
> (if extremely useful) part of a document type specification.
>
> Here's an example of a document type whose specification does not
> include a DTD:
>
>   Memo Document Type
>   ------------------
>
>   Every memo document consists of a root element named "memo"
>   with two element children: "number" and "body", optionally separated
>   by whitespace.  The contents of the "number" element shall be a
>   number between 1 and 99,999, assigned sequentially; the contents of
>   the "body" element shall be text containing a minimum of one and a
>   maximum of three sentences, using UK orthography.
>
> Here's a document conforming to that document type:
>
>   <?xml version="1.0"?>
>
>   <memo>
>    <number>2,126</number>
>    <body>Look, mum, no DTD!</body>
>   </memo>
>
> Now, I could have written a DTD and required its use as *part* of the
> document type specification:
>
>   <!ELEMENT memo (number, body)>
>   <!ELEMENT number (#PCDATA)>
>   <!ELEMENT body (#PCDATA)>
>
> However, it would be trivially easy to write documents that conform to
> the DTD but not to the document type:
>
>   <?xml version="1.0"?>
>
>   <!DOCTYPE memo SYSTEM "memo.dtd">
>
>   <memo>
>    <number>Let me not to the marriage of true minds</number>
>    <body>123</body>
>   </memo>
>
>
>
> All the best,
>
>
> David
>
> --
> David Megginson                 david@m...
>            http://www.megginson.com/
>
> xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i...
> Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on
CD-ROM/ISBN 981-02-3594-1
> To unsubscribe, mailto:majordomo@i... the following message;
> unsubscribe xml-dev
> To subscribe to the digests, mailto:majordomo@i... the following
message;
> subscribe xml-dev-digest
> List coordinator, Henry Rzepa (mailto:rzepa@i...)
>


xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i...
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on CD-ROM/ISBN 981-02-3594-1
To unsubscribe, mailto:majordomo@i... the following message;
unsubscribe xml-dev
To subscribe to the digests, mailto:majordomo@i... the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa@i...)



Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member