17 lines
289 B
Racket
17 lines
289 B
Racket
#lang typed/scheme
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(define key (gensym))
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(: eph-one (Ephemeronof Integer))
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(define eph-one (make-ephemeron key 1))
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(ephemeron? eph-one)
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(ephemeron-value eph-one)
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(: get-number ((Ephemeronof Number) -> Number))
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(define (get-number e)
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(or (ephemeron-value e) 0))
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(get-number eph-one)
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