Macros may be defined within the logic system using the form:
(defrelmacro < name > < arg-list > < body >) which is effectively the same as a Common Lisp defmacro . Logic macros are expanded before variable translation so that logic variables may be treated as atoms. d efrelmacro forms must have a fixed number of arguments. This allows different predicates with the same name but different aritys to be defined. If you want to define a special form with an arbitrary number of arguments, use defrel-special-form-macro .