8 lines
203 B
Text
8 lines
203 B
Text
import system.io
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open io
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variable [io.interface]
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def iowhen (b : bool) (a : io unit) : io unit :=
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if b = tt then a else return ()
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#eval iowhen tt (put_str "hello\n")
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#eval iowhen ff (put_str "error\n")
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