anchor.diff:  (in-package :clamp)
  +
  +(defparameter seconds-per-minute* 60 "The number of seconds per minute.")
  +(defparameter minutes-per-hour* 60 "The number of minutes per hour.")
  +(defparameter hours-per-day* 24 "The number of hours per day.")
   
   (mac time10 (expr)
     "Evaluates an expression 10 times and prints information about how
  
positive.code:     (list year month date)))
  
  (def datestring (&optional (time (seconds)))
    "Converts the given universal time into a string of the form 
     \"YYYY-MM-DD\". The default value is the current time."
    (tostring (apply #'prf "~4,'0D-~2,'0D-~2,'0D" (date time))))
  
negative.code: 
  (def minutes-since (t1)
    "Returns the number of minutes since universal time T1."
    (/ (since t1) seconds-per-minute*))
  
  (def hours-since (t1)
    "Returns the number of hours since universal time T1."
    (/ (minutes-since t1) minutes-per-hour*))
  
  (def days-since (t1)
    "Returns the number of days since universal time T1."
    (/ (hours-since t1) hours-per-day*))
  
  (def date (&optional (time (seconds)))
    "Converts the given universal time into a list containg the year,
  