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1. leftToMaybe :: Either l r -> Maybe l

   incipit-base	Incipit.Either

   Turn Left into Just and Right into Nothing.

2. rightToMaybe :: Either l r -> Maybe r

   incipit-base	Incipit.Either

   Turn Right into Just and Left into Nothing.

3. readMaybe :: Read a => String -> Maybe a

   incipit-base	Incipit.String.Reexport

   Parse a string using the Read instance. Succeeds if there is exactly one valid result.

   >>> readMaybe "123" :: Maybe Int
   Just 123
   

   >>> readMaybe "hello" :: Maybe Int
   Nothing
   

4. mapMaybeInput :: (Monoid s, Monoid s') => (s -> Maybe s') -> (s' -> Maybe s) -> Parser t s r -> Parser t s' r

   incremental-parser	Text.ParserCombinators.Incremental

   Converts a parser accepting one input type to another, just like 'mapMaybeInput except the two argument functions can demand more input by returning Nothing. If 'mapMaybeInput is defined for the two input inputs, then

   mapInput f g == mapMaybeInput (Just . f) (Just . g)
   

5. mapMaybeInput :: (Monoid s, Monoid s') => (s -> Maybe s') -> (s' -> Maybe s) -> Parser t s r -> Parser t s' r

   incremental-parser	Text.ParserCombinators.Incremental.LeftBiasedLocal

   Converts a parser accepting one input type to another, just like 'mapMaybeInput except the two argument functions can demand more input by returning Nothing. If 'mapMaybeInput is defined for the two input inputs, then

   mapInput f g == mapMaybeInput (Just . f) (Just . g)
   

6. mapMaybeInput :: (Monoid s, Monoid s') => (s -> Maybe s') -> (s' -> Maybe s) -> Parser t s r -> Parser t s' r

   incremental-parser	Text.ParserCombinators.Incremental.Symmetric

   Converts a parser accepting one input type to another, just like 'mapMaybeInput except the two argument functions can demand more input by returning Nothing. If 'mapMaybeInput is defined for the two input inputs, then

   mapInput f g == mapMaybeInput (Just . f) (Just . g)
   

7. readlineExMaybe :: String -> Maybe (CompletionEnv -> String -> IO ()) -> Maybe (String -> Fmt) -> IO (Maybe String)

   isocline	System.Console.Isocline

   As readlineEx but returns Nothing on end-of-file or other errors (ctrl-C/ctrl-D). See also readlineMaybe.

8. readlineMaybe :: String -> IO (Maybe String)

   isocline	System.Console.Isocline

   As readline but returns Nothing on end-of-file or other errors (ctrl-C/ctrl-D).

9. readlinePrimMaybe :: String -> Maybe (CompletionEnv -> String -> IO ()) -> Maybe (HighlightEnv -> String -> IO ()) -> IO (Maybe String)

   isocline	System.Console.Isocline

   As readlinePrim but returns Nothing on end-of-file or other errors (ctrl-C/ctrl-D). See also readlineMaybe.

10. showStrippedMaybe :: Show a => Either a JSAST -> String

    language-javascript	Language.JavaScript.Parser

    No documentation available.

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