16 lines
613 B
16 lines
613 B
2 years ago
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Exercise 3.8: When we defined the evaluation
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model in 1.1.3, we said that the first step in evaluating an
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expression is to evaluate its subexpressions. But we never specified the order
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in which the subexpressions should be evaluated (e.g., left to right or right
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to left). When we introduce assignment, the order in which the arguments to a
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procedure are evaluated can make a difference to the result. Define a simple
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procedure f such that evaluating
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(+ (f 0) (f 1))
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will return 0 if
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the arguments to + are evaluated from left to right but will return 1 if
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the arguments are evaluated from right to left.
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