22 lines
389 B
Scheme
22 lines
389 B
Scheme
(require (lib "gui.ss" "frtime"))
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(define op-names (list "+" "-" "*" "/"))
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(define ops (list + - * /))
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(define (str->num s)
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(cond
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[(string->number s)]
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[else 0]))
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(define x
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(str->num (make-text "First number:")))
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(define op
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(make-choice "Op:" op-names))
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(define y
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(str->num (make-text "Second number:")))
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(make-message
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(format "Result = ~a" ((list-ref ops op) x y)))
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