Safe Haskell	None
Language	Haskell2010

Vgrep.Event

Contents

Event handling
Dispatching Events
- Re-exports

Synopsis

data Next a
- = Skip
- | Continue a
- | Interrupt Interrupt
data Redraw
- = Redraw
- | Unchanged
data Interrupt
- = Suspend (forall m. MonadIO m => Environment -> m ())
- | Halt
dispatch :: (e -> Maybe a) -> e -> Next a
dispatchMap :: Ord e => Map e a -> e -> Next a
data Map k a
fromList :: Ord k => [(k, a)] -> Map k a

Event handling

An event handler is a function

handleEvent :: MonadState s m => e -> s -> Next (m Redraw)

where e is the event type and s is the state of the handler. The Next type determines the type of action to be performed. The state s is passed as a parameter so the handler can decide which type of action to perform, while not being able to modify the state.

Event handlers form a Monoid where the first handler that triggers will perform the action:

(handleSome <> handleOther) event state

is identical to

case handleSome event state of
    Skip -> handleOther event state
    action -> action

data Next a Source #

The type of action to be performed on an event.

Constructors

Skip	Do not handle the event (fall-through to other event handlers)
Continue a	Handle the event by performing an action
Interrupt Interrupt	Interrupt the application

Instances

Instances details

Functor Next Source #
Instance details Defined in Vgrep.Event Methods fmap :: (a -> b) -> Next a -> Next b # (<$) :: a -> Next b -> Next a #
Semigroup (Next a) Source #	The first event handler that triggers (i. e. does not return `Skip`) handles the event.
Instance details Defined in Vgrep.Event Methods (<>) :: Next a -> Next a -> Next a # sconcat :: NonEmpty (Next a) -> Next a # stimes :: Integral b => b -> Next a -> Next a #
Monoid (Next a) Source #
Instance details Defined in Vgrep.Event Methods mempty :: Next a # mappend :: Next a -> Next a -> Next a # mconcat :: [Next a] -> Next a #

data Redraw Source #

Constructors

Redraw	Indicates that the state has been changed visibly, so the screen should be refreshed.
Unchanged	The state has not changed or the change would not be visible, so refreshing the screen is not required.

Instances

Instances details

Semigroup Redraw Source #
Instance details Defined in Vgrep.Event Methods (<>) :: Redraw -> Redraw -> Redraw # sconcat :: NonEmpty Redraw -> Redraw # stimes :: Integral b => b -> Redraw -> Redraw #
Monoid Redraw Source #
Instance details Defined in Vgrep.Event Methods mempty :: Redraw # mappend :: Redraw -> Redraw -> Redraw # mconcat :: [Redraw] -> Redraw #

data Interrupt Source #

Constructors

Suspend (forall m. MonadIO m => Environment -> m ())	Suspend the application and run the action, e. g. invoking an external process, then resume the application.
Halt	Shut down.

Dispatching Events

dispatch :: (e -> Maybe a) -> e -> Next a Source #

If the lookup returns Just action, then handle it with Continue action', otherwise Skip this event handler.

dispatchMap :: Ord e => Map e a -> e -> Next a Source #

Special case of dispatch where actions are looked up from a map.

Re-exports

data Map k a #

A Map from keys k to values a.

The Semigroup operation for Map is union, which prefers values from the left operand. If m1 maps a key k to a value a1, and m2 maps the same key to a different value a2, then their union m1 <> m2 maps k to a1.

Instances

Instances details

Eq2 Map	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> Map a c -> Map b d -> Bool #
Ord2 Map	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) -> Map a c -> Map b d -> Ordering #
Show2 Map	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> Map a b -> ShowS # liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> [Map a b] -> ShowS #
Functor (Map k)
Instance details Defined in Data.Map.Internal Methods fmap :: (a -> b) -> Map k a -> Map k b # (<$) :: a -> Map k b -> Map k a #
Foldable (Map k)	Folds in order of increasing key.
Instance details Defined in Data.Map.Internal Methods fold :: Monoid m => Map k m -> m # foldMap :: Monoid m => (a -> m) -> Map k a -> m # foldMap' :: Monoid m => (a -> m) -> Map k a -> m # foldr :: (a -> b -> b) -> b -> Map k a -> b # foldr' :: (a -> b -> b) -> b -> Map k a -> b # foldl :: (b -> a -> b) -> b -> Map k a -> b # foldl' :: (b -> a -> b) -> b -> Map k a -> b # foldr1 :: (a -> a -> a) -> Map k a -> a # foldl1 :: (a -> a -> a) -> Map k a -> a # toList :: Map k a -> [a] # null :: Map k a -> Bool # length :: Map k a -> Int # elem :: Eq a => a -> Map k a -> Bool # maximum :: Ord a => Map k a -> a # minimum :: Ord a => Map k a -> a # sum :: Num a => Map k a -> a # product :: Num a => Map k a -> a #
Traversable (Map k)	Traverses in order of increasing key.
Instance details Defined in Data.Map.Internal Methods traverse :: Applicative f => (a -> f b) -> Map k a -> f (Map k b) # sequenceA :: Applicative f => Map k (f a) -> f (Map k a) # mapM :: Monad m => (a -> m b) -> Map k a -> m (Map k b) # sequence :: Monad m => Map k (m a) -> m (Map k a) #
(FromJSONKey k, Ord k) => FromJSON1 (Map k)
Instance details Defined in Data.Aeson.Types.FromJSON Methods liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Map k a) # liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Map k a] #
Eq k => Eq1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftEq :: (a -> b -> Bool) -> Map k a -> Map k b -> Bool #
Ord k => Ord1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftCompare :: (a -> b -> Ordering) -> Map k a -> Map k b -> Ordering #
(Ord k, Read k) => Read1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Map k a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Map k a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Map k a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Map k a] #
Show k => Show1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Map k a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Map k a] -> ShowS #
Ord k => IsList (Map k v)	Since: containers-0.5.6.2
Instance details Defined in Data.Map.Internal Associated Types type Item (Map k v) # Methods fromList :: [Item (Map k v)] -> Map k v # fromListN :: Int -> [Item (Map k v)] -> Map k v # toList :: Map k v -> [Item (Map k v)] #
(Eq k, Eq a) => Eq (Map k a)
Instance details Defined in Data.Map.Internal Methods (==) :: Map k a -> Map k a -> Bool # (/=) :: Map k a -> Map k a -> Bool #
(Data k, Data a, Ord k) => Data (Map k a)
Instance details Defined in Data.Map.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Map k a -> c (Map k a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Map k a) # toConstr :: Map k a -> Constr # dataTypeOf :: Map k a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Map k a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Map k a)) # gmapT :: (forall b. Data b => b -> b) -> Map k a -> Map k a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Map k a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Map k a -> r # gmapQ :: (forall d. Data d => d -> u) -> Map k a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Map k a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) #
(Ord k, Ord v) => Ord (Map k v)
Instance details Defined in Data.Map.Internal Methods compare :: Map k v -> Map k v -> Ordering # (<) :: Map k v -> Map k v -> Bool # (<=) :: Map k v -> Map k v -> Bool # (>) :: Map k v -> Map k v -> Bool # (>=) :: Map k v -> Map k v -> Bool # max :: Map k v -> Map k v -> Map k v # min :: Map k v -> Map k v -> Map k v #
(Ord k, Read k, Read e) => Read (Map k e)
Instance details Defined in Data.Map.Internal Methods readsPrec :: Int -> ReadS (Map k e) # readList :: ReadS [Map k e] # readPrec :: ReadPrec (Map k e) # readListPrec :: ReadPrec [Map k e] #
(Show k, Show a) => Show (Map k a)
Instance details Defined in Data.Map.Internal Methods showsPrec :: Int -> Map k a -> ShowS # show :: Map k a -> String # showList :: [Map k a] -> ShowS #
Ord k => Semigroup (Map k v)
Instance details Defined in Data.Map.Internal Methods (<>) :: Map k v -> Map k v -> Map k v # sconcat :: NonEmpty (Map k v) -> Map k v # stimes :: Integral b => b -> Map k v -> Map k v #
Ord k => Monoid (Map k v)
Instance details Defined in Data.Map.Internal Methods mempty :: Map k v # mappend :: Map k v -> Map k v -> Map k v # mconcat :: [Map k v] -> Map k v #
(FromJSONKey k, Ord k, FromJSON v) => FromJSON (Map k v)
Instance details Defined in Data.Aeson.Types.FromJSON Methods parseJSON :: Value -> Parser (Map k v) # parseJSONList :: Value -> Parser [Map k v] #
(NFData k, NFData a) => NFData (Map k a)
Instance details Defined in Data.Map.Internal Methods rnf :: Map k a -> () #
type Item (Map k v)
Instance details Defined in Data.Map.Internal type Item (Map k v) = (k, v)
type Index (Map k a)
Instance details Defined in Lens.Micro.GHC type Index (Map k a) = k
type IxValue (Map k a)
Instance details Defined in Lens.Micro.GHC type IxValue (Map k a) = a

fromList :: Ord k => [(k, a)] -> Map k a #

O(n*log n). Build a map from a list of key/value pairs. See also fromAscList. If the list contains more than one value for the same key, the last value for the key is retained.

If the keys of the list are ordered, linear-time implementation is used, with the performance equal to fromDistinctAscList.

fromList [] == empty
fromList [(5,"a"), (3,"b"), (5, "c")] == fromList [(5,"c"), (3,"b")]
fromList [(5,"c"), (3,"b"), (5, "a")] == fromList [(5,"a"), (3,"b")]