11 lines
296 B
11 lines
296 B
2 years ago
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Exercise 2.7: Alyssa’s program is incomplete
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because she has not specified the implementation of the interval abstraction.
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Here is a definition of the interval constructor:
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(define (make-interval a b) (cons a b))
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Define selectors upper-bound and lower-bound to complete the
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implementation.
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