This might also be worth a look:
Using tDOM and tDOM XSLT
A high-performance Tcl-scripted XSLT engine
http://www-106.ibm.com/developerworks/xml/library/x-tdom.html
tDOM is a high-performance, C-coded, DOM-oriented XML processor. tDOM XSLT is an XSLT engine built with tDOM that has extremely good performance in simple tests. tDOM and tDOM XSLT are open-source projects already in mission-critical production for several organizations. This article explains what you need to know to enjoy their advantages.
Simple benchmarks show that tDOM is one of the best-performing XML processors currently available. Access through the Tcl "scripting" language makes for a particularly potent development environment -- fast in both development and execution. A "dual level" (or two-language) model of development combines the advantages of Tcl and XSLT for different aspects of XML manipulation.
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Engineer Zoran Vasiljevic builds tDOM into AOLserver for very high performance DOM-based HTML generation.
