13 lines
261 B
Text
13 lines
261 B
Text
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; simplest
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(+ (read) (read))
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; safe
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(let ((a (read))
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(b (read)))
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(if (not (number? a))
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(runtime-error "a is not a number! got:" a))
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(if (not (number? b))
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(runtime-error "b is not a number! got:" b))
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(print a " + " b " = " (+ a b)))
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