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23 lines
659 B
23 lines
659 B
3 years ago
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Exercise 2.23: The procedure for-each is
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similar to map. It takes as arguments a procedure and a list of
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elements. However, rather than forming a list of the results, for-each
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just applies the procedure to each of the elements in turn, from left to right.
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The values returned by applying the procedure to the elements are not used at
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all—for-each is used with procedures that perform an action, such as
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printing. For example,
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(for-each
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(lambda (x) (newline) (display x))
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(list 57 321 88))
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57
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321
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88
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The value returned by the call to for-each (not illustrated above) can
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be something arbitrary, such as true. Give an implementation of
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for-each.
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