marketplace-2014/support/spy.rkt

#lang racket/base

(require "../sugar.rkt")

(provide generic-spy)

;; generic-spy : (All (ParentState) Any -> (Spawn ParentState))
(define (generic-spy label)
  (name-process `(generic-spy ,label)
    (spawn (transition (void)
	     (observe-publishers (wild)
	       (match-orientation orientation
		 (match-conversation topic
		   (match-interest-type interest
		     (match-reason reason
		       (on-presence (begin (write `(,label ENTER (,orientation ,topic ,interest)))
					   (newline)
					   (flush-output)
					   '()))
		       (on-absence (begin (write `(,label EXIT (,orientation ,topic ,interest)))
					  (newline)
					  (display reason)
					  (newline)
					  (flush-output)
					  '()))
		       (on-message
			[p (begin (write `(,label MSG ,p))
				  (newline)
				  (flush-output)
				  '())]))))))))))