xml-dev - Re: Extending DTDs for Backward Compatibility

[David Megginson <ak117@freenet.carleton.ca>]

Rick Jelliffe writes:

 > The first declaration of an entity has precedence.
 > 
 > So you can derive a new DTD by merely declaring the new
 > element types you need in the internal subset, and then
 > defining the appropriate parameter entity.

Absolutely right, but this doesn't solve his other problem -- that
processing software written for the base version of the DTD has to be
able to deal with documents written for the extended version.


All the best,


David

-- 
David Megginson                 ak117@freenet.carleton.ca
Microstar Software Ltd.         dmeggins@microstar.com
      http://home.sprynet.com/sprynet/dmeggins/

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