(mac let (parms val . body)
  `((fn (,parms) ,@body) ,val))

(mac macro args
  `(list 'lit 'mac (fn ,@args)))

(mac def (n . rest)
  `(set ,n (fn ,@rest)))

(mac mac (n . rest)
  `(set ,n (macro ,@rest)))

(mac or args
  (if (no args)
      nil
      (let v (uvar)
        `(let ,v ,(car args)
           (if ,v ,v (or ,@(cdr args)))))))

(mac and args
  (reduce (fn es (cons 'if es))
          (or args '(t))))