How much extra code for multiple Namespaces?

roddey at roddey at
Wed Sep 8 00:53:06 BST 1999

>From: <schen at>
>If you have such a mechanism then it should be fairly trivial to map all
>three XHTML namespaces into one, if as you say 99% of applications will
>treat them all the same anyway.  Then it is nowhere near the extra amount
>of code that you claim?  If you could, pls give an example!

The problem is that this is just one instance of this situation. If you allow it
here, will you make this the one and only special dispensation for it? If so,
then maybe all apps that deal with HTML can deal with this one case specially
and perhaps its no big deal (to me anyway, since I just write parsers :-)

But, if its not, how do you generalize it? Do you fill your XML processor with
lists of equivalent URLs, and tell it when and where they are really equivalent?
Otherwise, there is no way for a parser to validate such documents or even
confirm that it meets XML 1.0 rules (such as no reuse of the same attribute in
an element.)

And, even if you do this, you've put a big new burden on all processors to
support this kind of functionality. It will mean a performance hit because there
is no longer a unique string (uri-name, probably put into a pool and turned into
a single unique number) which represents an element or attribute. It would be a
significant change required in processors to handle this kind of thing.

Dean Roddey
Software Weenie
IBM Center for Java Technology - Silicon Valley
roddey at

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