e387279 · reflex-vty · git.iko.soy

29import Reflex.Host.Class

30import qualified Graphics.Vty as V

31

32−-- | The output of a 'VtyApp'

32+-- | The output of a 'VtyApp'.

33data VtyResult t = VtyResult

34 { _vtyResult_picture :: Behavior t V.Picture

35 -- ^ The current vty output. 'runVtyAppWith' samples this value every time an

38 -- ^ An event that requests application termination.

39 }

40

41−-- | A functional reactive vty application

41+-- | A functional reactive vty application.

42type VtyApp t m =

43 ( Reflex t

44 , MonadHold t m

51 , MonadRef (HostFrame t)

52 )

53 => Event t (V.Event)

54− -- ^ Vty input events

54+ -- ^ Vty input events.

55 -> TriggerEventT t (PostBuildT t (PerformEventT t m)) (VtyResult t)

56 -- ^ The output of the 'VtyApp'. The application runs in a context that

57 -- allows new events to be created and triggered ('TriggerEventT'), provides

59 -- ('PostBuildT'), and allows actions to be run upon occurrences

60 -- of events ('PerformEventT').

61

62−-- | Runs a 'VtyApp' in a given 'Vty'

62+-- | Runs a 'VtyApp' in a given 'Vty'.

63runVtyAppWith

64 :: V.Vty

65− -- ^ A 'Vty' handle

65+ -- ^ A 'Vty' handle.

66 -> (forall t m. VtyApp t m)

67− -- ^ A functional reactive vty application

67+ -- ^ A functional reactive vty application.

68 -> IO ()

69runVtyAppWith vty vtyGuest =

70 -- We are using the 'Spider' implementation of reflex. Running the host

91 -- result is a 'VtyResult', and a 'FireCommand' that will be used to

92 -- trigger events.

93 (vtyResult, fc@(FireCommand fire)) <- do

94− hostPerformEventT $ -- TODO document

94+ hostPerformEventT $ -- Allows the guest app to run

95+ -- 'performEvent', so that actions

96+ -- (e.g., IO actions) can be run when

97+ -- 'Event's fire.

95

98

96− flip runPostBuildT postBuild $ -- Runs the guest app in a context

99+ flip runPostBuildT postBuild $ -- Allows the guest app to access to

97− -- that provides access to a

98− -- "post-build" 'Event'

100+ -- a "post-build" 'Event'

99

101

100− flip runTriggerEventT events $ -- Runs the guest app in a context

102+ flip runTriggerEventT events $ -- Allows the guest app to create new

101− -- that allows new events and

102− -- triggers to be created and writes

103+ -- events and triggers and writes

103 -- those triggers to a channel from

104 -- those triggers to a channel from

104 -- which they will be read and

105 -- which they will be read and

105− -- triggered.

106+ -- processed.

106

107

107 vtyGuest vtyEvent -- The guest app is provided an

108 vtyGuest vtyEvent -- The guest app is provided an

108− -- 'Event' of vty inputs

109+ -- 'Event' of vty inputs.

109

110

110 -- Reads the current value of the 'Picture' behavior and updates the

111 -- Reads the current value of the 'Picture' behavior and updates the

111 -- display with it. This will be called whenever we determine that a

112 -- display with it. This will be called whenever we determine that a

152 -- have subscribers, and update the display. If we detect a shutdown

153 -- have subscribers, and update the display. If we detect a shutdown

153 -- request, the application terminates.

154 -- request, the application terminates.

154 fix $ \loop -> do

155 fix $ \loop -> do

155− -- Read the next event (blocking)

156+ -- Read the next event (blocking).

156 ers <- liftIO $ readChan events

157 ers <- liftIO $ readChan events

157 stop <- do

158 stop <- do

158 -- Fire events that have subscribers.

159 -- Fire events that have subscribers.

166 killThread nextEventThread -- then stop reading input events and

167 killThread nextEventThread -- then stop reading input events and

167 V.shutdown vty -- call the 'Vty's shutdown command.

168 V.shutdown vty -- call the 'Vty's shutdown command.

168

169

169− else do -- Otherwise, update the display and loop

170+ else do -- Otherwise, update the display and loop.

170 updateVty

171 updateVty

171 loop

172 loop

172 where

173 where