anchor.diff:  		       (rest ch))))
   
   
  -(defmethod schedule ((sce scenario) &rest events)
  +(defmethod schedule ((sce scenario) (events list))
     "Contract: scenario events -> scenario
   
      Purpose: to add the given events to the scenario, keeping them
  
positive.code:     :type time-type)
     (fn
      :initarg :fn
      :initform (error ":action missing")
      :accessor fn-of
      :type function)
     (args
  
negative.code: 
  ;; TODO
  
  (defpackage :org.altervista.rjack.de-sim
    (:nicknames :de-sim)
    (:use :common-lisp)
    (:export :id-type :time-type
  	   :object :id :id-of :parent :parent-of
  	   :simulator :clock :clock-of
  	   :scenario
  	   :event :owner-of :time-of :fn-of :args-of
  	   :port :lock-of :waiting-queue-of
  	   :in-port :out-port
  	   :i/o-transition-error
  	   :port-not-connected
  	   :out-port-busy
  	   :in-port-busy
  	   :wait :cancel
  	   :handle-input
  	   :connect-port :disconnect-port
  	   :lock-port :unlock-port
  	   :port-ready :access-port
  	   :output
  	   :add-child :remove-child :add-children :remove-children
  	   :schedule
  	   :evolving
  	   :evolve))
  (in-package :de-sim)
  
  
  