11 lines
364 B
Racket
11 lines
364 B
Racket
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(define-syntax-rule (define/atomic (name arg ...) E ...)
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(define name
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(let ([sema (make-semaphore 1)])
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(lambda (arg ...)
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(dynamic-wind (λ() (semaphore-wait sema))
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(λ() E ...)
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(λ() (semaphore-post sema)))))))
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;; this does the same as the above now:
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(define/atomic (foo x)
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(... do something ...))
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