This is a library of interactive processes combinators, usable to
define extensible keymaps.
(Inspired by the Parsec library, written by Koen Claessen)
The processes are:
- composable: in parallel using <|>, in sequence using monadic bind.
- extensible: it is always possible to override a behaviour by combination of
adjustPriority and <|>. (See also <|| for a convenient combination of the two.)
- monadic: sequencing is done via monadic bind. (leveraging the whole
battery of monadic tools that Haskell provides)
The processes can parse input, and write output that depends on it.
The semantics are quite obvious; only disjunction
deserve a bit more explanation:
in p = (a <|> b), what happens if a and b recognize the same
input (prefix), but produce conflicting output?
- if the output is the same (as by the PEq class), then the processes (prefixes) are merged
* if a Write is more prioritized than the other, the one with low priority will be discarded
* otherwise, the output will be delayed until one of the branches can be discarded.
* if there is no way to disambiguate, then no output will be generated anymore.
This situation can be detected by using possibleActions however.
|data I ev w a|
|class (PEq w, Monad m, Alternative m, Applicative m, MonadPlus m) => MonadInteract m w e | m -> w e where|
|class PEq a where|
|deprioritize :: MonadInteract f w e => f ()|
|(<||) :: MonadInteract f w e => f a -> f a -> f a|
|(||>) :: MonadInteract f w e => f a -> f a -> f a|
|option :: MonadInteract m w e => a -> m a -> m a|
|oneOf :: (Ord event, MonadInteract m w event) => [event] -> m event|
|processOneEvent :: PEq w => P event w -> event -> ([w], P event w)|
|computeState :: PEq w => P event w -> InteractState event w|
|event :: (Ord event, MonadInteract m w event) => event -> m event|
|events :: (Ord event, MonadInteract m w event) => [event] -> m [event]|
|choice :: MonadInteract m w e => [m a] -> m a|
|mkAutomaton :: PEq w => I ev w a -> P ev w|
|idAutomaton :: (Ord a, PEq a) => P a a|
|runWrite :: PEq w => P event w -> [event] -> [w]|
|anyEvent :: (Ord event, MonadInteract m w event) => m event|
|eventBetween :: (Ord e, MonadInteract m w e) => e -> e -> m e|
|accepted :: Show ev => Int -> P ev w -> [[String]]|
|Interactive process description
|Operational representation of a process
|forall mid . (Show mid, PEq mid) => Chain (P event mid) (P mid w)|
|data InteractState event w ||Source|
|Abstraction of the automaton state.
|Ambiguous [(Int, w, P event w)]|
|Running w (P event w)|
|Abstraction of monadic interactive processes
|Outputs a result.
|Consumes and returns the next character.
Fails if there is no input left, or outside the given bounds.
|option x p will either parse p or return x without consuming
|processOneEvent :: PEq w => P event w -> event -> ([w], P event w)||Source|
|Parses and returns the specified character.
|Parses and returns the specified list of events (lazily).
|Combines all parsers in the specified list.
|runWrite :: PEq w => P event w -> [event] -> [w]||Source|
|Produced by Haddock version 2.6.1|