Using sys.diana and sys.pidl to parse PL/SQL

It seems to me that it should be possible to parse existing PL/SQL with the packages sys.diana and sys.pidl, but I have found nothing on the internet with the exception of a few scripts that seem to unwrap a wrapped package (and that is useless for my purposes).

So, does anyone know about a pointer into the right direction?

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Like you, I've only heard of the concept in regards to reverse-engineering a wrapped package. In that line, maybe a post to Pete Finnigan's security forum might find someone who has done some work in that area. –  Gary Jan 28 '11 at 20:40
What is your goal in parsing the PL/SQL? –  Leigh Riffel Feb 1 '11 at 5:20
I have no specific goal in mind, I just thought it'd be nice to be able to read an already parsed syntax tree. It might be handy at some time in the future for something I don't no yet. –  René Nyffenegger Feb 1 '11 at 21:14
better late than never, found this presentation about reverse engineering pl/sql. petefinnigan.com/UnwrappingPLSQLBlackHat2006.pdf –  booyaa May 1 '14 at 12:22