Game.LambdaHack.Action

Game action monad and basic building blocks for player and monster actions.

Actions and basic operations

type ActionFun r a

Arguments

 = Session

session setup data

-> DungeonPerception

cached perception

-> (State -> Diary -> a -> IO r)

continuation

-> (Msg -> IO r)

failure/reset continuation

-> State

current state

-> Diary

current diary

-> IO r

The type of the function inside any action. (Separated from the Action type to document each argument with haddock.)

data Action a

Actions of player-controlled characters and of any other actors.

Instances

Monad Action

Functor Action

MonadState State Action

Show (Action a)

handlerToIO :: Session -> State -> Diary -> Action () -> IO ()

Run an action, with a given session, state and diary, in the IO monad.

rndToAction :: Rnd a -> Action a

Invoke pseudo-random computation with the generator kept in the state.

Actions returning frames

type ActionFrame a = Action (a, [Maybe SingleFrame])

Actions and screen frames, including delays, resulting from performing the actions.

returnNoFrame :: a -> ActionFrame a

Return the value with an empty set of screen frames.

whenFrame :: Bool -> ActionFrame () -> ActionFrame ()

As the when monad operation, but on type ActionFrame ().

inFrame :: Action () -> ActionFrame ()

Inject action into actions with screen frames.

Game session and its accessors

data Session

The constant session information, not saved to the game save file.

Constructors

Session

Fields

sfs :: FrontendSession

frontend session information

scops :: COps

game content

skeyb :: Binding (ActionFrame ())

binding of keys to commands

getCOps :: Action COps

Get the content operations.

getBinding :: Action (Binding (ActionFrame ()))

Get the key binding.

Various ways to abort action

abort :: Action a

Reset the state and resume from the last backup point, i.e., invoke the failure continuation.

abortWith :: Msg -> Action a

Abort with the given message.

abortIfWith :: Bool -> Msg -> Action a

Abort and print the given msg if the condition is true.

neverMind :: Bool -> Action a

Abort and conditionally print the fixed message.

Abort exception handlers

tryWith :: (Msg -> Action a) -> Action a -> Action a

Set the current exception handler. First argument is the handler, second is the computation the handler scopes over.

tryWithFrame :: Action a -> ActionFrame a -> ActionFrame a

Set the current exception handler. Apart of executing it, draw and pass along a frame with the abort message, if any.

tryRepeatedlyWith :: (Msg -> Action ()) -> Action () -> Action ()

Take a handler and a computation. If the computation fails, the handler is invoked and then the computation is retried.

tryIgnore :: Action () -> Action ()

Try the given computation and silently catch failure.

tryIgnoreFrame :: ActionFrame () -> ActionFrame ()

Try the given computation and silently catch failure, returning empty set of screen frames.

Diary and report

getDiary :: Action Diary

Get the current diary.

msgAdd :: Msg -> Action ()

Add a message to the current report.

recordHistory :: Action ()

Store current report in the history and reset report.

Key input

getKeyCommand :: Maybe Bool -> Action (Key, Modifier)

Wait for a player command.

getKeyChoice :: [(Key, Modifier)] -> SingleFrame -> Action (Key, Modifier)

Wait for a player keypress.

getOverConfirm :: [SingleFrame] -> Action Bool

A series of confirmations for all overlays.

Display each frame and confirm

displayMore :: ColorMode -> Msg -> Action Bool

Display a msg with a more prompt. Return value indicates if the player tried to cancel/escape.

displayYesNo :: Msg -> Action Bool

Print a yes/no question and return the player's answer. Use black and white colours to turn player's attention to the choice.

displayOverAbort :: Msg -> [Overlay] -> Action ()

Print a msg and several overlays, one per page. All frames require confirmations. Raise abort if the players presses ESC.

Assorted frame operations

displayOverlays :: Msg -> [Overlay] -> ActionFrame ()

Print a msg and several overlays, one per page. The last frame does not expect a confirmation.

displayChoiceUI :: Msg -> [Overlay] -> [(Key, Modifier)] -> Action (Key, Modifier)

Print a prompt and an overlay and wait for a player keypress. If many overlays, scroll screenfuls with SPACE. Do not wrap screenfuls (in some menus ? cycles views, so the user can restart from the top).

displayFramePush :: Maybe SingleFrame -> Action ()

Push a frame or a single frame's worth of delay to the frame queue.

drawPrompt :: ColorMode -> Msg -> Action SingleFrame

Draw the current level. The prompt is displayed, but not added to history. The prompt is appended to the current message and only the first screenful of the resulting overlay is displayed.

Clip init operations

startClip :: Action () -> Action ()

Initialize perception, etc., display level and run the action.

remember :: Action ()

Update player memory.

rememberList :: [Point] -> Action ()

Update player at the given list of locations..

Assorted operations

getPerception :: Action Perception

Get the current perception.

updateAnyActor :: ActorId -> (Actor -> Actor) -> Action ()

Update actor stats. Works for actors on other levels, too.

updatePlayerBody :: (Actor -> Actor) -> Action ()

Update player-controlled actor stats.

Assorted primitives

currentDate :: Action ClockTime

Obtains the current date and time.

saveGameBkp :: State -> Diary -> Action ()

Save the diary and a backup of the save game file, in case of crashes.

See saveGameBkp.

dumpCfg :: FilePath -> CP -> Action ()

Dumps the current configuration to a file.

See dump.

shutGame :: (Bool, Status) -> Action ()

End the game, shutting down the frontend. The boolean argument tells if ending screens should be shown, the other arguments describes the cause of shutdown.

debug :: String -> Action ()

Debugging.