37 lines
860 B
Scheme
37 lines
860 B
Scheme
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(module constants mzscheme
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(provide
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dummy
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dummy-thunk
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undefined
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thunk-empty
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thunk-false
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test-true
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test-false
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id
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(rename void-cst void)
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select-right
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select-left
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;car!
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;cdr!
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)
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(define dummy (void))
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(define dummy-thunk (lambda () dummy))
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(define undefined (letrec ([x x]) x))
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(define thunk-empty (lambda () '()))
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(define thunk-false (lambda () #f))
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(define test-true (lambda (x) #t))
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(define test-false (lambda (x) #f))
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(define id (lambda (x) x))
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(define void-cst (void))
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(define select-right (lambda (x y) y))
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(define select-left (lambda (x y) x))
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;(define car! (case-lambda
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; [(pair) (car pair)]
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; [(pair val) (set-car! pair val)]))
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;(define cdr! (case-lambda
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; [(pair) (cdr pair)]
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; [(pair val) (set-cdr! pair val)]))
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)
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