Why doesn't XML have Bag?

[Andrew McNaughton]

> Matt,
> 
> Then let me ask another question - why do DTDs not allow me to specify
> an unordered list of elements?  For example, 
> 
> <!ELEMENT Kitchen RDF:Bag(Sink, Stove, Refrigerator)>
> 
> With this notation I am trying to indicate that an XML document that
> conforms to this DTD must have a <Kitchen> element which has three child
> elements - <Sink>, <Stove>, and <Refrigerator>, and these child elements
> can be in any order.  Isn't this a useful thing?  I have had a number of
> times where I wish that I could do this.

Is it a useful thing?  It might be nice for humans entering the data to be unconstrained in the order in which they can enter data, but if you know exactly what elements must exist within kitchen, then does it limit you to pre-define the order they appear in the document.

I suppose if you want the order to denote something about the position of the elements within your physical kitchen, then you've lost something, but attributes are probably a better solution for storing this information about the elements within your kitchen.

Andrew McNaughton 





-- 
-----------
Andrew McNaughton
andrew at squiz.co.nz
http://www.newsroom.co.nz/



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