This problem exists, but it is equivalent to problems Common Lisp programmer has to face if he writes macros, and solutions are similar. In CL it is solved with

This problem exists, but it is equivalent to problems Common Lisp programmer has to face if he writes macros, and solutions are similar. In CL it is solved with gensyms, and Scheme hygienic macros automatised that. Similar approaches are possible - and practiced - in Newlisp.