34 lines
1022 B
Racket
34 lines
1022 B
Racket
#lang racket/base
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;; Test the existence of forged generic functions for
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;; gen:custom-write and gen:equal+hash
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(require racket/generic)
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(struct tuple (ref)
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#:methods gen:custom-write
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[(define/generic super write-proc)
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(define (write-proc v p w)
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(super v p w))]
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#:methods gen:equal+hash
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[(define/generic super-eq equal-proc)
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(define/generic hash1 hash-proc)
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(define/generic hash2 hash2-proc)
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(define (equal-proc a b e)
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(super-eq (tuple-ref a) (tuple-ref b) e))
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(define (hash-proc a h)
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(hash1 (tuple-ref a) h))
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(define (hash2-proc a h)
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(hash2 (tuple-ref a) h))])
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(module+ test
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(require rackunit racket/port)
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;; ok if these don't raise unbound id errors
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(check-equal? (with-output-to-string (lambda () (write (tuple 5)))) "#0=#0#")
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(check-equal? (tuple 5) (tuple 5))
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(check-equal? (equal-hash-code (tuple 5))
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(equal-hash-code (tuple 5)))
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(check-equal? (equal-secondary-hash-code (tuple 5))
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(equal-secondary-hash-code (tuple 5))))
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