> For the model you described above, you don't need Prolog to implement > it. Since there's no backtracking involved, you can model the > resources as a dependency graph, aka a directed graph. To resolve the > dependencies, just sort it topologically and traverse it > postorder. This is exactly the same mechanism implemented by the Unix > make or Jakarta's Ant.
I'm wondering if this is a weakness in my example, or if Ant really is sufficient. > Prolog is useful for more complex activities, that require > backtracking, but I'm not sure how practical this option is in a Web > environment, considering the fact that backtracking means essentially > throwing away computation done to resolve a dependency. That is an excellent point that I hadn't considered. All of the caching in the world won't help if you're always throwing away all of your work. This raises the interesting possibility of replacing sitemap.xsl with the Ant engine. Jason Foster --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, email: [EMAIL PROTECTED]