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Also a good one would be XML::Twig module for Perl, which allows the loading of only those nodes that are needed. Ilya > -----Original Message----- > From: Nicolas Lehuen [mailto:nicolas.lehuen@u...] > Sent: Friday, January 25, 2002 2:14 PM > To: Clark C . Evans; Sterin, Ilya > Cc: xml-dev@l... > Subject: Re: Push and Pull? > > > SAXDOMIX [1] could be classified as semi-random-access, > push-flow-control-interface. It enables you to parse a > document in the SAX model, and switch when desired to the DOM > model to build partial trees that are pushed into a > controller. It is semi-random access because you have full > random access on the partial trees, but sequential access > between them. > > dom4j also implements this idea, in a less generic way (but > much more simple and easy to use), and calls it 'tree pruning' [2]. > > This approach is quite interesting for XML document with a > fixed-depth repetitive structure, such as a list of elements > with a complex structure. It simplifies your code by making > it possible to use tree accessors (imagine how it would be > great with dom4j XPath accessors !), instead of having to > deal with a stack and/or a state-machine, without forcing the > whole document to be loaded in memory. > > Regards, > Nicolas > > > [1] http://www.devsphere.com/xml/saxdomix/ > [2] > http://dom4j.org/faq.html#How%20does%20dom4j%20handle%20very%2 > 0large%20XML%2 > 0documents? > > N.B. the anchor contains a '?', so the link is not valid in > Outlook Express. Sigh. > > ----- Original Message ----- > From: "Clark C . Evans" <cce@c...> > To: "Sterin, Ilya" <Isterin@c...> > Cc: <xml-dev@l...> > Sent: Friday, January 25, 2002 8:01 PM > Subject: Re: Push and Pull? > > > > On Fri, Jan 25, 2002 at 11:29:51AM -0700, Sterin, Ilya wrote: > > | >In SAX, the parser is has the > > | >control loop and thus this makes SAX parsers easy to > write. In DOM > > | >the control loop is owned by the library's user. > > | > > | That said, it again brings us down to that SAX parsers all (most) > > | follow the push model, and DOM based follow the pull model. > > > > DOM [1] uses a random-access, pull-flow-control interface. > > SAX [2] uses a sequential-access, push-flow-control > interface. XPP [3] > > uses a sequential-access, pull-flow-control interface. > > > > | > I've only just begun playing with random access push models... > > | > this is more or less events that can be replayed > > | > > | For the push model to be replayed, probably means that it > will have > > | to keep a parts in memory, or reparse all over again? > > > > Yes. To offer random access an interface will probably > elect to keep > > an in-memory representation. Although a random access > interface could > > be done over a database (see Tamino), etc. > > > > | This means that we are back to in memory parsers right, > or is there > > | some other concept behind it? > > > > Right. The examples above give you 3 permutations, one > > could develop an interface which used random-access but > > push-flow-control. I started to put together an interface for this > > about a year back... it had a way for events > > to be "re-played". I stopped after I didn't see an > > obvious application of the technique. > > > > ;) Clark > > > > [1] http://www.w3.org/DOM/ > > [2] http://www.saxproject.org/ > > [1] http://www.extreme.indiana.edu/soap/xpp/ > > > > -- > > Clark C. Evans Axista, Inc. > > http://www.axista.com 800.926.5525 > > XCOLLA Collaborative Project Management Software > > > > ----------------------------------------------------------------- > > The xml-dev list is sponsored by XML.org <http://www.xml.org>, an > > initiative of OASIS <http://www.oasis-open.org> > > > > The list archives are at http://lists.xml.org/archives/xml-dev/ > > > > To subscribe or unsubscribe from this list use the subscription > > manager: <http://lists.xml.org/ob/adm.pl> > > >
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