9 lines
229 B
Scheme
9 lines
229 B
Scheme
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; Copyright (c) 1993-1999 by Richard Kelsey and Jonathan Rees. See file COPYING.
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(define (make-weak-pointer x) (cons '<weak> x))
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(define weak-pointer-ref cdr)
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(define (weak-pointer? x)
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(and (pair? x) (eq? (car x) '<weak>)))
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