Function: LIST-MATCH

Source

(defun list-match (x y &optional binds)
  (acond2
    ((or (eql x y) (eql x '_) (eql y '_))
     (values binds t))
    ((binding x binds) (list-match it y binds))
    ((binding y binds) (list-match x it binds))
    ((varsymp x) (values (cons (cons x y) binds) t))
    ((varsymp y) (values (cons (cons y x) binds) t))
    ((and (consp x) (consp y) (list-match (car x) (car y) binds))
     (list-match (cdr x) (cdr y) it))
    (t (values nil nil))))