20 lines
557 B
Racket
20 lines
557 B
Racket
#lang syndicate
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;; Hello-worldish "bank account" example.
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(require syndicate/actor)
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(struct account (balance) #:prefab)
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(struct deposit (amount) #:prefab)
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(actor (forever #:collect [(balance 0)]
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(assert (account balance))
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(on (message (deposit $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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(actor (until (asserted (observe (deposit _))))
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(send! (deposit +100))
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(send! (deposit -30)))
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