Interesting. So we can compute source code!

What's the equivalent of this: take code and double the numbers in it, then execute it:

    CL-USER 33 > (eval (mapcar (lambda (atom)
                                 (typecase atom
                                   (number (expt atom 2))
                                   (t      atom)))
                               (cons '*
                                     (list 3 4 5))))
    3600