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Within LTS Haskell 24.4 (ghc-9.10.2)

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1. maybeTagText :: Tag str -> Maybe str

   tagsoup	Text.HTML.TagSoup

   Extract the string from within TagText, otherwise Nothing

2. maybeTagWarning :: Tag str -> Maybe str

   tagsoup	Text.HTML.TagSoup

   Extract the string from within TagWarning, otherwise Nothing

3. maybeToList :: Maybe a -> [a]

   strict	Data.Strict.Maybe

   Analogous to maybeToList in Data.Maybe.

4. maybeCodec :: ValueCodec input output -> ValueCodec (Maybe input) (Maybe output)

   autodocodec	Autodocodec

   Maybe codec This can be used to also allow null during decoding of a Maybe value. During decoding, also accept a null value as Nothing. During encoding, encode as usual.

   Example usage

   >>> toJSONVia (maybeCodec codec) (Just 'a')
   String "a"
   
   >>> toJSONVia (maybeCodec codec) (Nothing :: Maybe Char)
   Null
   

5. maybeCodec :: ValueCodec input output -> ValueCodec (Maybe input) (Maybe output)

   autodocodec	Autodocodec.Codec

   Maybe codec This can be used to also allow null during decoding of a Maybe value. During decoding, also accept a null value as Nothing. During encoding, encode as usual.

   Example usage

   >>> toJSONVia (maybeCodec codec) (Just 'a')
   String "a"
   
   >>> toJSONVia (maybeCodec codec) (Nothing :: Maybe Char)
   Null
   

6. maybeToLeft :: b -> Maybe a -> Either a b

   either	Data.Either.Combinators

   Maybe produce a Left, otherwise produce a Right.

   >>> maybeToLeft "default" (Just 12)
   Left 12
   

   >>> maybeToLeft "default" Nothing
   Right "default"
   

7. maybeToRight :: b -> Maybe a -> Either b a

   either	Data.Either.Combinators

   Maybe produce a Right, otherwise produce a Left.

   >>> maybeToRight "default" (Just 12)
   Right 12
   

   >>> maybeToRight "default" Nothing
   Left "default"
   

8. maybeAbort :: Exceptional e a -> Maybe e -> Exceptional e a

   explicit-exception	Control.Monad.Exception.Asynchronous.Lazy

   No documentation available.

9. maybeAbort :: Exceptional e a -> Maybe e -> Exceptional e a

   explicit-exception	Control.Monad.Exception.Asynchronous.Strict

   No documentation available.

10. maybeToList :: Maybe a -> [a]

    rio	RIO.Prelude

    The maybeToList function returns an empty list when given Nothing or a singleton list when given Just.

    Examples

    Basic usage:

    >>> maybeToList (Just 7)
    [7]
    

    >>> maybeToList Nothing
    []
    

    One can use maybeToList to avoid pattern matching when combined with a function that (safely) works on lists:

    >>> import GHC.Internal.Text.Read ( readMaybe )
    
    >>> sum $ maybeToList (readMaybe "3")
    3
    
    >>> sum $ maybeToList (readMaybe "")
    0
    

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