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28 lines
753 B
28 lines
753 B
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Exercise 3.37: The
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celsius-fahrenheit-converter procedure is cumbersome when compared with
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a more expression-oriented style of definition, such as
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(define (celsius-fahrenheit-converter x)
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(c+ (c* (c/ (cv 9) (cv 5))
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x)
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(cv 32)))
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(define C (make-connector))
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(define F (celsius-fahrenheit-converter C))
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Here c+, c*, etc. are the “constraint” versions of the
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arithmetic operations. For example, c+ takes two connectors as
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arguments and returns a connector that is related to these by an adder
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constraint:
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(define (c+ x y)
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(let ((z (make-connector)))
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(adder x y z)
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z))
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Define analogous procedures c-, c*, c/, and cv
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(constant value) that enable us to define compound constraints as in the
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converter example above.161
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