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1. maybeFromByteString :: ByteString -> T T

   midi	Sound.MIDI.Message

   No documentation available.

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

   ghc-internal	GHC.Internal.Data.Maybe

   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
   

3. maybeNew :: (a -> IO (Ptr b)) -> Maybe a -> IO (Ptr b)

   ghc-internal	GHC.Internal.Foreign.Marshal.Utils

   Allocate storage and marshal a storable value wrapped into a Maybe

   • the nullPtr is used to represent Nothing

4. maybePeek :: (Ptr a -> IO b) -> Ptr a -> IO (Maybe b)

   ghc-internal	GHC.Internal.Foreign.Marshal.Utils

   Convert a peek combinator into a one returning Nothing if applied to a nullPtr

5. maybeWith :: (a -> (Ptr b -> IO c) -> IO c) -> Maybe a -> (Ptr b -> IO c) -> IO c

   ghc-internal	GHC.Internal.Foreign.Marshal.Utils

   Converts a withXXX combinator into one marshalling a value wrapped into a Maybe, using nullPtr to represent Nothing.

6. maybeLens :: b -> Lens' (Maybe b) b

   proto-lens	Data.ProtoLens.Message

   A helper lens for accessing optional fields. This is used as part of code generation, and should generally not be needed explicitly. Note that maybeLens does not satisfy the lens laws, which expect that set l (view l x) == x. For example,

   set (maybeLens 'a') (view (maybeLens 'a') Nothing) == Just 'a'
   

   However, this is the behavior generally expected by users, and only matters if we're explicitly checking whether a field is set.

7. maybeToEnum :: MessageEnum a => Int -> Maybe a

   proto-lens	Data.ProtoLens.Message

   Convert the given Int to an enum value. Returns Nothing if no corresponding value was defined in the .proto file.

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

   protolude	Protolude

   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
   

9. maybeEmpty :: Monoid b => (a -> b) -> Maybe a -> b

   protolude	Protolude.Either

   No documentation available.

10. maybeToEither :: e -> Maybe a -> Either e a

    protolude	Protolude.Either

    No documentation available.

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