[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: Walking the DOM (was: XML APIs)

• From: John Cowan <cowan@l...>
• To: XML Dev <xml-dev@i...>
• Date: Fri, 13 Nov 1998 11:21:03 -0500

Miles Sabin wrote:

> OK, I agree that this check is O(1). However, that's only
> because the granularity of the check is so coarse: a single
> document-level timestamp will cause a lot of unnecessary
> invalidation ...

Agreed.  But this isn't so important if there are few active
iterators (= iterators that will ever be resumed), which was my
point.

> I suspect that it would make the performance
> of modifying a document via iterators unacceptably poor.

Here I think the JDK 1.2 java.util.Iterator class is useful: it has
a "remove" method which removes the last element iterated to
in a safe way, or raises an exception if the underlying
container is read-only.
 
> Moving to per-node timestamps would reduce the amount of
> unnecessary invalidation, and preserve the O(1) check,
> but at the cost of making tree modifications O(log n).

Just so.

-- 
John Cowan	http://www.ccil.org/~cowan		cowan@c...
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i...
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/
To (un)subscribe, mailto:majordomo@i... the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo@i... the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa@i...)

• Prev by Date: Re: SAX Future
• Next by Date: Re: SAX Future
• Previous by thread: Re: Walking the DOM (was: XML APIs)
• Next by thread: Re: Specifying virtual fonts in XML for handling variant characters
• Index(es):
  • Date
  • Thread