Bob believes that Alice wants to meet him, and Alice knows this, but in fact Alice wants to avoid Bob.
(define (sample-location)
(if (flip .55)
'good-bar
'bad-bar))
(define (alice* depth)
(rejection-query
(define alice*-location (sample-location))
alice*-location
(not (equal? alice*-location (bob (- depth 1))))))
(define (alice depth)
(rejection-query
(define alice-location (sample-location))
alice-location
(equal? alice-location (bob (- depth 1)))))
(define (bob depth)
(rejection-query
(define bob-location (sample-location))
bob-location
(if (= depth 0)
#t
(equal? bob-location (alice depth)))))
(hist (repeat 10 (lambda () (alice* 3))))
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