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| Code Block |
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(define-struct sum (left right)) (define-struct prod (left right)) (define-struct diff (left right)) (define-struct quot (left right)) |
an ArithExpr ArithExpr is either:
- a number
n, - a sum
(make-sum ae1 ae2), - a product
(make-prod ae1 ae2), - a difference
(make-diff ae1 ae2), or - a quotient
(make-quot ae1 ae2)
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