18 lines
450 B
Racket
18 lines
450 B
Racket
#lang typed/syndicate
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(require rackunit/turnstile)
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(check-type empty-sequence : (Sequence (U)))
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(check-type (sequence-length empty-sequence)
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: Int
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⇒ 0)
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(define sequence-length/Int (inst sequence-length Int))
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(define sequence->list/Int (inst sequence->list Int))
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(define in-list/Int (inst in-list Int))
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(check-type (sequence->list/Int (in-list/Int (list 3 9 20)))
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: (List Int)
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⇒ (list 3 9 20))
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