ATTN: Please comment on XHTML (before it's too late)

Paul Prescod paul at
Mon Aug 30 01:17:16 BST 1999

Tim Bray wrote:
> HTML4 has 3 DTDs.  That certainly doesn't mean it's 3 languages.  

What definition of language are you using? What are the properties of a
language? I claim that a language has three properties:

1. vocubulary
2. grammar
3. semantics

HTML4 has 3 different vocabularies (two are presumably subsets). HTML4
has 3 different grammars (ditto). 

Insofar as nobody can define semantics and computers don't work with
them, common semantics are irrelevant. Otherwise we could claim that
Cold Fusion Markup Language (CFML) and HTML should share a namespace
because all of the HTML element types share semantics with some CFML
element types. Or DTML and HTML. Or even TEI and HTML or ...

Some of the referents of names in some of these namespaces may
interchangable. We need a way to say that explicitly.

>  It's
> routine for a language to have multiple DTDs for different purposes.
> It's surprising for it to have 3 names. -T.

Until recently our only name for languages *was* the DTD's public or
system identifier. Therefore it has been routine for similar languages
to have differing names:

PUBLIC "-//TEI//DTD TEI Lite 1.5 //EN" "pubtext/teilite.dtd"
PUBLIC "-//TEI//DTD TEI Lite 1.6//EN" "pubtext/teilite.dtd"

PUBLIC "-//W3C//DTD HTML 4.0//EN" strict.dtd
PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" pubtext\html\html4.dtd
PUBLIC "-//W3C//DTD HTML 4.0 Frameset//EN" frameset.dtd

PUBLIC "ISO 8879-1986//ENTITIES Added Latin 1//EN" 
PUBLIC "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML" 

 Paul Prescod

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at
Archived as: and on CD-ROM/ISBN 981-02-3594-1
To (un)subscribe, mailto:majordomo at the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at

More information about the Xml-dev mailing list