| Copyright | Daan Leijen 1999-2001 Bryan O'Sullivan 2007-2015 |
|---|---|
| License | BSD3 |
| Maintainer | bos@serpentine.com |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Data.Attoparsec.Combinator
Contents
Description
Useful parser combinators, similar to those provided by Parsec.
- try :: Parser i a -> Parser i a
- (<?>) :: Parser i a -> String -> Parser i a
- choice :: Alternative f => [f a] -> f a
- count :: Monad m => Int -> m a -> m [a]
- option :: Alternative f => a -> f a -> f a
- many' :: MonadPlus m => m a -> m [a]
- many1 :: Alternative f => f a -> f [a]
- many1' :: MonadPlus m => m a -> m [a]
- manyTill :: Alternative f => f a -> f b -> f [a]
- manyTill' :: MonadPlus m => m a -> m b -> m [a]
- sepBy :: Alternative f => f a -> f s -> f [a]
- sepBy' :: MonadPlus m => m a -> m s -> m [a]
- sepBy1 :: Alternative f => f a -> f s -> f [a]
- sepBy1' :: MonadPlus m => m a -> m s -> m [a]
- skipMany :: Alternative f => f a -> f ()
- skipMany1 :: Alternative f => f a -> f ()
- eitherP :: Alternative f => f a -> f b -> f (Either a b)
- feed :: Monoid i => IResult i r -> i -> IResult i r
- satisfyElem :: forall t. Chunk t => (ChunkElem t -> Bool) -> Parser t (ChunkElem t)
- endOfInput :: forall t. Chunk t => Parser t ()
- atEnd :: Chunk t => Parser t Bool
- lookAhead :: Parser i a -> Parser i a
Combinators
try :: Parser i a -> Parser i a Source #
Attempt a parse, and if it fails, rewind the input so that no input appears to have been consumed.
This combinator is provided for compatibility with Parsec. attoparsec parsers always backtrack on failure.
Arguments
| :: Parser i a | |
| -> String | the name to use if parsing fails |
| -> Parser i a |
Name the parser, in case failure occurs.
choice :: Alternative f => [f a] -> f a Source #
choice ps tries to apply the actions in the list ps in order,
until one of them succeeds. Returns the value of the succeeding
action.
count :: Monad m => Int -> m a -> m [a] Source #
Apply the given action repeatedly, returning every result.
option :: Alternative f => a -> f a -> f a Source #
option x p tries to apply action p. If p fails without
consuming input, it returns the value x, otherwise the value
returned by p.
priority = option 0 (digitToInt <$> digit)
many' :: MonadPlus m => m a -> m [a] Source #
many' p applies the action p zero or more times. Returns a
list of the returned values of p. The value returned by p is
forced to WHNF.
word = many' letter
many1 :: Alternative f => f a -> f [a] Source #
many1 p applies the action p one or more times. Returns a
list of the returned values of p.
word = many1 letter
many1' :: MonadPlus m => m a -> m [a] Source #
many1' p applies the action p one or more times. Returns a
list of the returned values of p. The value returned by p is
forced to WHNF.
word = many1' letter
manyTill :: Alternative f => f a -> f b -> f [a] Source #
manyTill p end applies action p zero or more times until
action end succeeds, and returns the list of values returned by
p. This can be used to scan comments:
simpleComment = string "<!--" *> manyTill anyChar (string "-->")
(Note the overlapping parsers anyChar and string "-->".
While this will work, it is not very efficient, as it will cause a
lot of backtracking.)
manyTill' :: MonadPlus m => m a -> m b -> m [a] Source #
manyTill' p end applies action p zero or more times until
action end succeeds, and returns the list of values returned by
p. This can be used to scan comments:
simpleComment = string "<!--" *> manyTill' anyChar (string "-->")
(Note the overlapping parsers anyChar and string "-->".
While this will work, it is not very efficient, as it will cause a
lot of backtracking.)
The value returned by p is forced to WHNF.
sepBy :: Alternative f => f a -> f s -> f [a] Source #
sepBy p sep applies zero or more occurrences of p, separated
by sep. Returns a list of the values returned by p.
commaSep p = p `sepBy` (char ',')
sepBy' :: MonadPlus m => m a -> m s -> m [a] Source #
sepBy' p sep applies zero or more occurrences of p, separated
by sep. Returns a list of the values returned by p. The value
returned by p is forced to WHNF.
commaSep p = p `sepBy'` (char ',')
sepBy1 :: Alternative f => f a -> f s -> f [a] Source #
sepBy1 p sep applies one or more occurrences of p, separated
by sep. Returns a list of the values returned by p.
commaSep p = p `sepBy1` (char ',')
sepBy1' :: MonadPlus m => m a -> m s -> m [a] Source #
sepBy1' p sep applies one or more occurrences of p, separated
by sep. Returns a list of the values returned by p. The value
returned by p is forced to WHNF.
commaSep p = p `sepBy1'` (char ',')
skipMany :: Alternative f => f a -> f () Source #
Skip zero or more instances of an action.
skipMany1 :: Alternative f => f a -> f () Source #
Skip one or more instances of an action.
eitherP :: Alternative f => f a -> f b -> f (Either a b) Source #
Combine two alternatives.
feed :: Monoid i => IResult i r -> i -> IResult i r Source #
If a parser has returned a Partial result, supply it with more
input.
satisfyElem :: forall t. Chunk t => (ChunkElem t -> Bool) -> Parser t (ChunkElem t) Source #
The parser satisfyElem p succeeds for any chunk element for which the
predicate p returns True. Returns the element that is
actually parsed.
endOfInput :: forall t. Chunk t => Parser t () Source #
Match only if all input has been consumed.