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Within LTS Haskell 24.38 (ghc-9.10.3)

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1. leftToMaybe :: Either a b -> Maybe a

   rebase	Rebase.Prelude

   Maybe get the Left side of an Either.

   leftToMaybe ≡ either Just (const Nothing)
   

   Using Control.Lens:

   leftToMaybe ≡ preview _Left
   leftToMaybe x ≡ x^?_Left
   

   >>> leftToMaybe (Left 12)
   Just 12
   

   >>> leftToMaybe (Right 12)
   Nothing
   

2. mapMaybeT :: (m (Maybe a) -> n (Maybe b)) -> MaybeT m a -> MaybeT n b

   rebase	Rebase.Prelude

   Transform the computation inside a MaybeT.

   • runMaybeT (mapMaybeT f m) = f (runMaybeT
     m)

3. readMaybe :: Read a => String -> Maybe a

   rebase	Rebase.Prelude

   Parse a string using the Read instance. Succeeds if there is exactly one valid result.

   >>> readMaybe "123" :: Maybe Int
   Just 123
   

   >>> readMaybe "hello" :: Maybe Int
   Nothing
   

4. rightToMaybe :: Either a b -> Maybe b

   rebase	Rebase.Prelude

   Maybe get the Right side of an Either.

   rightToMaybe ≡ either (const Nothing) Just
   

   Using Control.Lens:

   rightToMaybe ≡ preview _Right
   rightToMaybe x ≡ x^?_Right
   

   >>> rightToMaybe (Left 12)
   Nothing
   

   >>> rightToMaybe (Right 12)
   Just 12
   

5. runMaybeApply :: MaybeApply (f :: Type -> Type) a -> Either (f a) a

   rebase	Rebase.Prelude

   No documentation available.

6. mapMaybe :: forall (m :: Type -> Type) cl a b . Monad m => ClSF m cl a b -> ClSF m cl (Maybe a) (Maybe b)

   rhine	FRP.Rhine.ClSF.Core

   Call a ClSF every time the input is 'Just a'. Caution: This will not change the time differences since the last tick. For example, while integrate 1 is approximately the same as timeInfoOf sinceInit, mapMaybe $ integrate 1 is very different from mapMaybe $ timeInfoOf sinceInit. The former only integrates when the input is Just 1, whereas the latter always returns the correct time since initialisation.

7. throwMaybe :: forall (m :: Type -> Type) e cl a . Monad m => ClSF (ExceptT e m) cl (Maybe e) (Maybe a)

   rhine	FRP.Rhine.ClSF.Except

   When the input is Just e, throw the exception e.

8. emitSMaybe :: forall (m :: Type -> Type) event cl . MonadIO m => ClSF (EventChanT event m) cl (Maybe event) ()

   rhine	FRP.Rhine.Clock.Realtime.Event

   Emit an event whenever the input value is Just event.

9. emitSMaybe' :: forall event (m :: Type -> Type) cl . (NFData event, MonadIO m) => ClSF (EventChanT event m) cl (Maybe event) ()

   rhine	FRP.Rhine.Clock.Realtime.Event

   Like emitSMaybe, but completely evaluates the event before emitting it.

10. satisfyMaybe :: (Word8 -> Bool) -> Scanner (Maybe Word8)

    scanner	Scanner

    Consume a single octet in case it satisfies the predicate

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