16 lines
549 B
Scheme
16 lines
549 B
Scheme
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;;; -*-Scheme-*-
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;;;
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;;; This macro evaluates its arguments (arbitrary expressions) in a
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;;; lexical environment created as a copy of the global environment
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;;; in which all the predefined primitives are bound.
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;;; Contributed by Carsten Bormann <cabo@informatik.uni-bremen.de>
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(define-macro (with-safe-environment . body)
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(let* ((built-in-environment
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(car (last-pair (environment->list (the-environment)))))
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(binding-copy
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(map (lambda (p)
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(list (car p) (car p)))
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built-in-environment)) )
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`(let ,binding-copy ,@body)))
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