33 lines
864 B
Racket
33 lines
864 B
Racket
#lang typed/syndicate/roles
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(define-constructor (account balance)
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#:type-constructor AccountT
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#:with Account (AccountT Int)
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#:with AccountRequest (AccountT ★/t))
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(define-constructor (deposit amount)
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#:type-constructor DepositT
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#:with Deposit (DepositT Int)
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#:with DepositRequest (DepositT ★/t))
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(define-type-alias ds-type
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(U Account
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(Observe AccountRequest)
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(Observe (Observe AccountRequest))
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Deposit
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(Observe DepositRequest)
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(Observe (Observe DepositRequest))))
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(spawn ds-type
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(print-role
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(start-facet account-manager
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(fields [balance Int 0])
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(assert (account (ref balance)))
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(on (asserted (deposit (bind amount Int)))
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(set! balance (+ (ref balance) amount))))))
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(spawn ds-type
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(start-facet observer
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(fields)
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(on (asserted (account (bind amount Int)))
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(displayln amount)))) |