9 lines
277 B
Text
9 lines
277 B
Text
(defun eval-subtract-for-two-values-of-x (code-fragment x1 x0)
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(let ((e1 (make-env))
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(e0 (make-env)))
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(env-vbind e1 'x x1)
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(env-vbind e0 'x x0)
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(- (eval code-fragment e1)
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(eval code-fragment e0))))
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(eval-subtract-for-two-values-of-x '(exp x) 1 2)
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