Arthur Barraux
34 lines
575 B
Scheme
34 lines
575 B
Scheme
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; QUASIQUOTE
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(assert (equal? `(1 2 3) '(1 2 3)))
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(let ((x 1))
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(assert (equal? `(,x 2 3) '(1 2 3))))
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(let ((x 'a))
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(assert (equal? `(,x x ,x) '(a x a))))
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; nil! macro
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(define-macro nil! (lambda (x)
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`(set! ,x '())))
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(define x 3)
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(assert (= x 3))
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(nil! x)
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(assert (null? x))
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; ntimes macro
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(define-macro ntimes (lambda (n . body)
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(let ((i (gensym)))
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(cons 'DO (cons `((,i 0 (+ ,i 1)))
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(cons `((>= ,i ,n) '()) body))
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))))
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(define x 0)
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(ntimes 10 (set! x (+ x 1)))
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(assert (= x 10))
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