(defn log
  "Print the message with current *name* as a label."
  [message]
  (println (str *name* ": " message)))


(defmacro defthread
  "Define object flow in new thread and
   binds *name*."
  [thread-name & body]
  `(def ~thread-name
     (quote
      (binding [*name* ~(name thread-name)]
        (future ~@body)))))

(defn begin
  "First message in thread."
  [message]
  (log (str message " ●")))

(defn end
  "Last message in thread."
  [message]
  (log (str message ". ○")))

(defthread client
  (begin "Pay")
  (>!! m1 1)
  (log "Wait for cheque")
  (<!! m2)
  (log "Get cheque")
  (log "Give cheque to reception")
  (>!! s1 1)
  (log "Wait for goods and warranty")
  (<!! m7)
  (end "Get goods and warranty"))