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1. VariantClassMaybe :: VariantClass

   gi-glib	GI.GLib.Enums

   The GVariant is a maybe-typed value.

2. variantTypeIsMaybe :: (HasCallStack, MonadIO m) => VariantType -> m Bool

   gi-glib	GI.GLib.Structs.VariantType

   Determines if the given type is a maybe type. This is true if the type string for type starts with an 'm'. This function returns True for any indefinite type for which every definite subtype is a maybe type -- G_VARIANT_TYPE_MAYBE, for example.

3. variantTypeNewMaybe :: (HasCallStack, MonadIO m) => VariantType -> m VariantType

   gi-glib	GI.GLib.Structs.VariantType

   Constructs the type corresponding to a maybe instance containing type type or Nothing. It is appropriate to call variantTypeFree on the return value.

4. combSpanMaybe :: SrcSpanInfo -> Maybe SrcSpanInfo -> SrcSpanInfo

   haskell-src-exts	Language.Haskell.Exts.SrcLoc

   Like (<+?>), but it also concatenates the srcInfoPoints.

5. contramapMaybe :: (a -> Maybe b) -> OutputStream b -> IO (OutputStream a)

   io-streams	System.IO.Streams.Combinators

   Contravariant counterpart to contramapMaybe. contramap f s passes all input to s through the function f. Discards all the elements for which f returns Nothing. Since: 1.2.1.0

6. mapMaybe :: (a -> Maybe b) -> InputStream a -> IO (InputStream b)

   io-streams	System.IO.Streams.Combinators

   A version of map that discards elements mapMaybe f s passes all output from s through the function f and discards elements for which f s evaluates to Nothing. Example:

   ghci> Streams.fromList [Just 1, None, Just 3] >>=
   Streams.mapMaybe id >>=
   Streams.toList
   [1,3]
   

   Since: 1.2.1.0

7. catMaybes :: [Maybe a] -> [a]

   strict	Data.Strict.Maybe

   Analogous to catMaybes in Data.Maybe.

8. fromMaybe :: a -> Maybe a -> a

   strict	Data.Strict.Maybe

   Given a default value and a Maybe, yield the default value if the Maybe argument is Nothing and extract the value out of the Just otherwise.

9. listToMaybe :: [a] -> Maybe a

   strict	Data.Strict.Maybe

   Analogous to listToMaybe in Data.Maybe.

10. mapMaybe :: (a -> Maybe b) -> [a] -> [b]

    strict	Data.Strict.Maybe

    Analogous to mapMaybe in Data.Maybe.

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