Canonical AST, the only Abstract Syntax Tree you need, with importers+exporters to all languages (planned)
Currently used by English script, Angle language and as a Ruby to python converter. See ast-export.rb and ast_import.py ! Todo: cleanup, improve, write connectors for jvm/java clr/csharp
AST Treenode specification: see XML/XSD, kast.py and kast.rb, inspired and mostly based on pythons ast!