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1. maybeName :: a -> Bool -> Maybe a

   dbus	DBus.Generation

   No documentation available.

2. maybeParseString :: Parser a -> String -> Maybe a

   dbus	DBus.Internal.Address

   No documentation available.

3. maybeParseString :: MonadThrow m => Parser a -> String -> m a

   dbus	DBus.Internal.Types

   No documentation available.

4. maybeEndOfExecutable :: String -> IO (Maybe String)

   end-of-exe	EndOfExe2

   Can be used instead of os to check whether the executable ends in ".exe". The function returns IO Nothing if there is neither ys nor (ys ++ ".exe") names for executables in the search path. It can also search in other locations and its behaviour is OS dependent. For more information, please, refer to the link: https://hackage.haskell.org/package/directory-1.3.4.0/docs/System-Directory.html#v:findExecutable For more information, how the executable is searched, see also the following address: https://hackage.haskell.org/package/process-1.6.18.0/docs/System-Process.html#t:CmdSpec

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

   foundation	Foundation

   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
   

6. maybeRecord :: PersistableType q => RecordFromSql q a -> ColumnConstraint NotNull a -> RecordFromSql q (Maybe a)

   persistable-record	Database.Record.FromSql

   Derivation rule of RecordFromSql parser function object for Haskell Maybe type.

7. maybeWidth :: PersistableRecordWidth a -> PersistableRecordWidth (Maybe a)

   persistable-record	Database.Record.Persistable

   Derivation rule of PersistableRecordWidth from from Haskell type a into for Haskell type Maybe a.

8. maybeToExceptT :: forall (m :: Type -> Type) e a . Functor m => e -> MaybeT m a -> ExceptT e m a

   rebase	Rebase.Prelude

   Convert a MaybeT computation to ExceptT, with a default exception value.

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

   rebase	Rebase.Prelude

   Maybe produce a Left, otherwise produce a Right.

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

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

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

    rebase	Rebase.Prelude

    Maybe produce a Right, otherwise produce a Left.

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

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

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