Data::Transformator, Data::Merger, Data::Comparator perform intelligent operations on nested perl data structures. The transformation engine is a general simple transformation engine and can run in a selective mode or a constructive mode. In the selective mode, it behaves like a database query engine. In the constructive mode it constructs a result based on the structure of the original data. Transformations can be cascaded. The merger also deals with general nested perl data structures. The Comparator generates structured differences that mirror the structure of the compared data structures. To install the module... perl Makefile.PL make make test make install If you are on a windows box you should use 'nmake' rather than 'make'.