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22 lines
470 B
22 lines
470 B
2 years ago
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Exercise 4.6: Let expressions are derived
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expressions, because
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(let ((⟨var₁⟩ ⟨exp₁⟩) … (⟨varₙ⟩ ⟨expₙ⟩))
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⟨body⟩)
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is equivalent to
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((lambda (⟨var₁⟩ … ⟨varₙ⟩)
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⟨body⟩)
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⟨exp₁⟩
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…
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⟨expₙ⟩)
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Implement a syntactic transformation let->combination that reduces
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evaluating let expressions to evaluating combinations of the type shown
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above, and add the appropriate clause to eval to handle let
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expressions.
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