23 lines
649 B
Racket
23 lines
649 B
Racket
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#lang prospect
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;; Hello-worldish "bank account" example.
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(require prospect/actor)
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(struct account (balance) #:prefab)
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(struct alter-balance-by (amount) #:prefab)
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(actor-body->spawn-action
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(lambda ()
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(actor (forever #:collect [(balance 0)]
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(assert (account balance))
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(on (message (alter-balance-by $amount))
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(+ balance amount))))
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(actor (forever (on (asserted (account $balance))
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(printf "Balance changed to ~a\n" balance))))
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(until (asserted (observe (alter-balance-by _))))
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(send! (alter-balance-by +100))
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(send! (alter-balance-by -30))
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))
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