c24650ef01
* sigma, gamma extended at expand time * All type-checking happens at expand time * Locally expand all forms into core redex forms. However, this seems to be causing problems. Probably not controlling expansion just right.
35 lines
738 B
Racket
35 lines
738 B
Racket
#lang s-exp "cur-redex.rkt"
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(require "sugar.rkt")
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(module+ test
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(require rackunit))
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(data nat : Type
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(z : nat)
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(s : (-> nat nat)))
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(define (add1 (n : nat)) (s n))
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(module+ test
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(check-equal? (add1 (s z)) (s (s z))))
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(define (sub1 (n : nat))
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(case n
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[z z]
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[s (lambda (x : nat) x)]))
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(module+ test
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;; TODO: Um. For some reason, sigma becomes empty here?
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(check-equal? (sub1 (s z)) z))
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(define plus
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(fix (plus : (forall* (n1 : nat) (n2 : nat) nat))
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(lambda (n1 : nat)
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(lambda (n2 : nat)
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(case n1
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[z n2]
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[s (λ (x : nat) (plus x (s n2)))])))))
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(module+ test
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(check-equal? (plus z z) z)
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(check-equal? (plus (s (s z)) (s (s z))) (s (s (s (s z))))))
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(add1 (s z))
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(sub1 (s z))
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