[XML-SIG] DOM Extension Proposal

Uche Ogbuji uogbuji@fourthought.com
Sun, 25 Jun 2000 09:19:36 -0600

> * Mike Olson
> | 
> | We inherit NamedNodeMap from UserDict now so we are not too far off. 
> | However, we do return the Attribute node.  I suppose we could override
> | this to return just the value of the node.
> | 
> | Anyone else's thoughts?
> I have been wondering why we even have Attribute nodes in the DOM tree
> at all. They are mainly useful for representing entity references in
> attribute values, something that is very rarely useful. :-) 
> So I think there would be definite performance benefits (in terms of
> both speed and memory use) in keeping a dictionary of names -> string
> values instead of names -> nodes.
> Attribute nodes could be lazily instantiated when someone calls
> getAttributeNode. If we want to support entity references inside
> attributes we can do this by using lists in the dictionary for those
> cases instead of strings. Most likely this would be used in much less
> than 1% of the cases and I wouldn't complain if we decided not to
> support this stuff at all.

This is exactly an optimization we have in mind for 4DOM 1.0, inspired by a 
similar enhancement in Xalan's DOM.

Uche Ogbuji                               Principal Consultant
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