Halogen.Query.EventSource

newtype EventSource f m

Constructors

• EventSource (m { producer :: Producer (f SubscribeStatus) m Unit, done :: m Unit })

data SubscribeStatus

The status of an EventSource subscription. When a query raised by an EventSource evaluates to Done the producer will be unsubscribed from.

Constructors

• Listening
• Done

Instances

• Eq SubscribeStatus
• Ord SubscribeStatus

unEventSource :: forall f m. EventSource f m -> m { producer :: Producer (f SubscribeStatus) m Unit, done :: m Unit }

interpret :: forall f g m. Functor m => (f ~> g) -> EventSource f m -> EventSource g m

hoist :: forall f m n. Functor n => (m ~> n) -> EventSource f m -> EventSource f n

eventSource :: forall f m a. MonadAff m => ((a -> Effect Unit) -> Effect Unit) -> (a -> Maybe (f SubscribeStatus)) -> EventSource f m

Creates an EventSource for a callback that accepts one argument.

• The first argument is the function that attaches the listener.
• The second argument is a handler that optionally produces a value in f.

eventSource' :: forall f m a. MonadAff m => ((a -> Effect Unit) -> Effect (Effect Unit)) -> (a -> Maybe (f SubscribeStatus)) -> EventSource f m

Similar to eventSource but allows the attachment function to return an action to perform when the handler is detached.

eventSource_ :: forall f m. MonadAff m => (Effect Unit -> Effect Unit) -> f SubscribeStatus -> EventSource f m

Creates an EventSource for a callback that accepts no arguments.

• The first argument is the function that attaches the listener.
• The second argument is the query to raise whenever the listener is triggered.

eventSource_' :: forall f m. MonadAff m => (Effect Unit -> Effect (Effect Unit)) -> f SubscribeStatus -> EventSource f m

Similar to eventSource_ but allows the attachment function to return an action to perform when the handler is detached.

catMaybes :: forall m a r. MonadRec m => Producer (Maybe a) m r -> Producer a m r

Takes a producer of Maybes and filters out the Nothings. Useful for constructing EventSources for producers that don't need to handle every event.

produce :: forall a r. ((Either a r -> Effect Unit) -> Effect Unit) -> Producer a Aff r

produce' :: forall a r. ((Either a r -> Effect Unit) -> Effect (Effect Unit)) -> Aff { producer :: Producer a Aff r, cancel :: r -> Aff Boolean }

produceAff :: forall a r m. MonadAff m => ((Either a r -> Aff Unit) -> Aff Unit) -> Producer a m r

produceAff' :: forall a r. ((Either a r -> Aff Unit) -> Aff (Aff Unit)) -> Aff { producer :: Producer a Aff r, cancel :: r -> Aff Boolean }