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28 lines
692 B
28 lines
692 B
2 years ago
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Exercise 4.28: Eval uses
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actual-value rather than eval to evaluate the operator before
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passing it to apply, in order to force the value of the operator. Give
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an example that demonstrates the need for this forcing.
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Exercise 4.29: Exhibit a program that you would
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expect to run much more slowly without memoization than with memoization.
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Also, consider the following interaction, where the id procedure is
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defined as in Exercise 4.27 and count starts at 0:
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(define (square x) (* x x))
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;;; L-Eval input:
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(square (id 10))
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;;; L-Eval value:
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⟨response⟩
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;;; L-Eval input:
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count
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;;; L-Eval value:
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⟨response⟩
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Give the responses both when the evaluator memoizes and when it does not.
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