Data.Conduit.Parser

This module introduces ConduitParser, a wrapper around Sink that behaves like a parser.

You probably want to import the Text.Parser.Combinators module together with this module.

Conduit parser monad

data ConduitParser i m a

Core type of the package. This is basically a Sink with a parsing state.

Instances

MonadError ConduitParserException (ConduitParser i m)

Backtracking is supported by pushing back consumed elements (using leftover) whenever an error is catched.

As a consequence, within the scope of a catchError, all streamed items are kept in memory, which means the consumer no longer uses constant memory.

Methods

throwError :: ConduitParserException -> ConduitParser i m a

catchError :: ConduitParser i m a -> (ConduitParserException -> ConduitParser i m a) -> ConduitParser i m a

MonadTrans (ConduitParser i)

Methods

lift :: Monad m => m a -> ConduitParser i m a

Monad (ConduitParser i m)

Methods

(>>=) :: ConduitParser i m a -> (a -> ConduitParser i m b) -> ConduitParser i m b

(>>) :: ConduitParser i m a -> ConduitParser i m b -> ConduitParser i m b

return :: a -> ConduitParser i m a

fail :: String -> ConduitParser i m a

Functor (ConduitParser i m)

Methods

fmap :: (a -> b) -> ConduitParser i m a -> ConduitParser i m b

(<$) :: a -> ConduitParser i m b -> ConduitParser i m a

Applicative (ConduitParser i m)

Methods

pure :: a -> ConduitParser i m a

(<*>) :: ConduitParser i m (a -> b) -> ConduitParser i m a -> ConduitParser i m b

liftA2 :: (a -> b -> c) -> ConduitParser i m a -> ConduitParser i m b -> ConduitParser i m c

(*>) :: ConduitParser i m a -> ConduitParser i m b -> ConduitParser i m b

(<*) :: ConduitParser i m a -> ConduitParser i m b -> ConduitParser i m a

Alternative (ConduitParser i m)

Parsers can be combined with (<|>), some, many, optional, choice.

The use of guard is not recommended as it generates unhelpful error messages. Please consider using throwError or unexpected instead.

Methods

empty :: ConduitParser i m a

(<|>) :: ConduitParser i m a -> ConduitParser i m a -> ConduitParser i m a

some :: ConduitParser i m a -> ConduitParser i m [a]

many :: ConduitParser i m a -> ConduitParser i m [a]

MonadIO m => MonadIO (ConduitParser i m)

Methods

liftIO :: IO a -> ConduitParser i m a

MonadThrow m => MonadThrow (ConduitParser i m)

Methods

throwM :: Exception e => e -> ConduitParser i m a

Monad m => Parsing (ConduitParser i m)

Parsing combinators can be used with ConduitParsers.

Methods

try :: ConduitParser i m a -> ConduitParser i m a

(<?>) :: ConduitParser i m a -> String -> ConduitParser i m a

skipMany :: ConduitParser i m a -> ConduitParser i m ()

skipSome :: ConduitParser i m a -> ConduitParser i m ()

unexpected :: String -> ConduitParser i m a

eof :: ConduitParser i m ()

notFollowedBy :: Show a => ConduitParser i m a -> ConduitParser i m ()

runConduitParser :: MonadThrow m => ConduitParser i m a -> ConduitT i Void m a

Run a ConduitParser. Any parsing failure will be thrown as an exception.

named :: Monad m => Text -> ConduitParser i m a -> ConduitParser i m a

Flipped version of (<?>).

Primitives

await :: Monad m => ConduitParser i m i

await wrapped as a ConduitParser.

If no data is available, UnexpectedEndOfInput is thrown.

leftover :: i -> ConduitParser i m ()

leftover wrapped as a ConduitParser.

getParserNames :: ConduitParser i m [Text]

Return the ordered list of names (assigned through (<?>)) for the current parser stack. First element is the most nested parser.

getParserName :: ConduitParser i m Text

Return the name (assigned through (<?>)) of the current parser (most nested), or mempty if it has none.

Utility

peek :: Monad m => ConduitParser i m (Maybe i)

peek wrapped as a ConduitParser.

Exception

data ConduitParserException

Constructors

BothFailed ConduitParserException ConduitParserException

ExpectedEndOfInput

NamedParserException Text ConduitParserException

UnexpectedEndOfInput

UnexpectedFollowedBy Text

Unexpected Text

Instances

Eq ConduitParserException

Methods

(==) :: ConduitParserException -> ConduitParserException -> Bool

(/=) :: ConduitParserException -> ConduitParserException -> Bool

Show ConduitParserException

Methods

showsPrec :: Int -> ConduitParserException -> ShowS

show :: ConduitParserException -> String

showList :: [ConduitParserException] -> ShowS

Exception ConduitParserException

Methods

toException :: ConduitParserException -> SomeException

fromException :: SomeException -> Maybe ConduitParserException

displayException :: ConduitParserException -> String

MonadError ConduitParserException (ConduitParser i m)

Backtracking is supported by pushing back consumed elements (using leftover) whenever an error is catched.

As a consequence, within the scope of a catchError, all streamed items are kept in memory, which means the consumer no longer uses constant memory.

Methods

throwError :: ConduitParserException -> ConduitParser i m a

catchError :: ConduitParser i m a -> (ConduitParserException -> ConduitParser i m a) -> ConduitParser i m a