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22 lines
561 B
22 lines
561 B
2 years ago
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Exercise 5.41: Write a procedure
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find-variable that takes as arguments a variable and a compile-time
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environment and returns the lexical address of the variable with respect to
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that environment. For example, in the program fragment that is shown above,
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the compile-time environment during the compilation of expression ⟨e1⟩ is
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((y z) (a b c d e) (x y)). Find-variable should produce
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(find-variable
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'c '((y z) (a b c d e) (x y)))
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(1 2)
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(find-variable
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'x '((y z) (a b c d e) (x y)))
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(2 0)
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(find-variable
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'w '((y z) (a b c d e) (x y)))
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not-found
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