The wrong model at the wrong level of abstraction? (Score 1)

Having access to the parse tree is only valuable to a point, and in Lisp you have to use MOP to do more. Most of the limits in software complexity and maintainablity are in the relationship that span the branches of the tree, and are not made explicit in in tree itself. You don't want to do code generation such 'this interface has a "visit" method for each leaf subclass of class in this package' using XSLT or any other tree based model; either you have a relational model, or you have to write masses of tree navigation code. In terms of parsing and storage, if the common syntactic model was expressed as ASN.1, then both the Java syntax and the XML syntax could be encodings of the same abstract model, and you could use whatever tool you liked, and store the code in whatever form you like.