(defmacro generate-lambda (lambda-list body)
  `#'(lambda ,lambda-list ,body))
(defmacro partial-aux (func &rest args)
  (with-gensyms (function new-args llist)
    `(let ((,function ,func)
	   (,new-args (mapcar #'eval ',args)))
       (let ((,llist (nthcdr (length ,new-args)
			     (stop-at-special (sb-introspect:function-lambda-list ,function)))))
	 `(generate-lambda ,,llist (funcall ,,function ,@(append ,new-args ,llist)))))))
(defmacro partial (func &rest args)
  (eval `(partial-aux ,func ,@args))) ;; Example call: (funcall (partial #'subst 1 2) '(1 2 3)) --> (1 1 3)
(defun stop-at-special (list &optional acc)
  (if (or (null list)
	  (some #'(lambda (y) (equalp (car list) y))
		'(&key &optional)));Deliberately breaks on &rest and &body.
      (reverse acc)
      (stop-at-special (cdr list) (cons (car list) acc))))
(defmacro with-gensyms (symbols &body body)
  `(let (,@(mapcar #'(lambda (sym)
		       `(,sym ',(gensym))) symbols))
     ,@body))