Design

• Several XSLT stylesheets managed via several xsl-stylesheet processing instructions
• two stylesheets applied in pipe: one for querying the data, one for formatting
• the XPath generator GUI makes use of object-oriented Javascript programming (Reference book: Javascript - the definite guide, by David Flanagan - O'Reilly publisher) and has an object Model of an XPath query
• use of the terminal part of the URL to obtain the URL of the XML data, e.g..:
  http://wwbota.free.fr/Generic/XMLClient.htm?URL=http://www.mycom.com/mydata.xml?xpath=/*/*[1]
  This is used in the reverse way to the normal use (from URL to browser, instead of from browser to server via URL)
• use of CBE Javascript library to achieve portability between DOM 2 and Internet Explorer : Cross-Browser.com : CBE is a Cross-Browser DHTML API for IE
• reference for XSLT in Javascipt on Mozilla
  

Possible enhancements

• enhance ergonomy
• better representation of the schema (maybe with embeded HTML lists, using this stylesheet generating schema out of an XML instance) , enabling use of a skeleton DOM document to record the structure of the instance document, instead of the simple associative array with XPath strings that is currently used.
• Add buttons : "Remove XPath Step" "Remove XPath constraint"
• refactoring necessary at top-level