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22 lines
408 B
Idris
22 lines
408 B
Idris
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import Data.Maybe
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%default total
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FromString Int where
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fromString x = cast x
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test1 : Int
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test1 = "42"
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test2 : Int
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test2 = "abc"
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convert : String -> Maybe Bool
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convert "True" = Just True
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convert "False" = Just False
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convert _ = Nothing
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fromString : (str : String) -> {auto prf : IsJust (convert str)} -> Bool
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fromString str {prf} with (convert str)
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fromString str {prf = ItIsJust} | (Just ret) = ret
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