14 lines
246 B
Racket
14 lines
246 B
Racket
#lang typed/racket
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(: f (case->
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(-> Boolean)
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(Input-Port -> Boolean)
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(Bytes -> Boolean)))
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(define (f (p #f))
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(cond ((input-port? p) #t)
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((bytes? p) #f)
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(else #f)))
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(assert (call-with-input-bytes #"port" f))
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