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

   classy-prelude-yesod	ClassyPrelude.Yesod

   The mapMaybe function is a version of map which can throw out elements. In particular, the functional argument returns something of type Maybe b. If this is Nothing, no element is added on to the result list. If it is Just b, then b is included in the result list.

   Examples

   Using mapMaybe f x is a shortcut for catMaybes $ map f x in most cases:

   >>> import GHC.Internal.Text.Read ( readMaybe )
   
   >>> let readMaybeInt = readMaybe :: String -> Maybe Int
   
   >>> mapMaybe readMaybeInt ["1", "Foo", "3"]
   [1,3]
   
   >>> catMaybes $ map readMaybeInt ["1", "Foo", "3"]
   [1,3]
   

   If we map the Just constructor, the entire list should be returned:

   >>> mapMaybe Just [1,2,3]
   [1,2,3]
   

2. mapOutputMaybe :: forall (m :: Type -> Type) o1 o2 i r . Monad m => (o1 -> Maybe o2) -> ConduitT i o1 m r -> ConduitT i o2 m r

   classy-prelude-yesod	ClassyPrelude.Yesod

   Same as mapOutput, but use a function that returns Maybe values. Since 0.5.0

3. runMaybeC :: forall (m :: Type -> Type) i o r . Monad m => ConduitT i o (MaybeT m) r -> ConduitT i o m (Maybe r)

   classy-prelude-yesod	ClassyPrelude.Yesod

   Run MaybeT in the base monad Since 1.0.11

4. queryMaybe :: forall (m :: Type -> Type) world a . Monad m => (world 'FieldOf -> Maybe a) -> QueryT world m (Maybe a)

   ecstasy	Data.Ecstasy

   Attempt to get the value of a component.

5. queryMaybe :: forall (m :: Type -> Type) world a . Monad m => (world 'FieldOf -> Maybe a) -> QueryT world m (Maybe a)

   ecstasy	Data.Ecstasy.Internal

   Attempt to get the value of a component.

6. class ReifyMaybeSymbol (mstr :: Maybe Symbol)

   generic-data-functions	Generic.Data.Function.Traverse.Constructor

   No documentation available.

7. reifyMaybeSymbol :: ReifyMaybeSymbol mstr => Maybe String

   generic-data-functions	Generic.Data.Function.Traverse.Constructor

   No documentation available.

8. isClassOpId_maybe :: Id -> Maybe Class

   ghc-lib	GHC

   No documentation available.

9. synTyConDefn_maybe :: TyCon -> Maybe ([TyVar], Type)

   ghc-lib	GHC

   Extract the TyVars bound by a vanilla type synonym and the corresponding (unsubstituted) right hand side.

10. synTyConRhs_maybe :: TyCon -> Maybe Type

    ghc-lib	GHC

    Extract the information pertaining to the right hand side of a type synonym (type) declaration.

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