(load "functions.lisp")

;; This is based on the dlambda macro presented in "Let Over Lambda" by Doug Hoyte.

(let
  ((add-method-clause
    (lambda (method)
      (cons (first method)
        (list
          (cons 'apply
            (cons (cons 'lambda (rest method))
              (list
                (if (equal t (car method))
                  'arguments
                  '(rest arguments))))))))))

  (defmacro dlambda (&rest methods)
    (cons 'lambda
      (cons '(&rest arguments)
        (list
          (cons 'case
            (cons '(first arguments)
              (mapcar add-method-clause methods))))))))