Pipes.Attoparsec

pipes utilities for incrementally running attoparsec-based parsers.

This module assumes familiarity with pipes-parse, you can learn about it in Pipes.Parse.Tutorial.

Parsing

parse

Arguments

:: (Monad m, ParserInput a)

=> Parser a b

Attoparsec parser

-> Parser a m (Maybe (Either ParsingError b))

Pipes parser

Convert an attoparsec Parser to a pipes-parse Parser.

This Parser is compatible with the tools from Pipes.Parse.

It returns Nothing if the underlying Producer is exhausted, otherwise it attempts to run the given attoparsec Parser on the underlying Producer, possibly failing with ParsingError.

parsed

Arguments

:: (Monad m, ParserInput a)

=> Parser a b

Attoparsec parser

-> Producer a m r

Raw input

-> Producer b m (Either (ParsingError, Producer a m r) r)

Convert a producer of ParserInput to a producer of parsed values.

This producer returns Right when end-of-input is reached sucessfully, otherwise it returns a ParsingError and the leftovers including the malformed input that couldn't be parsed. You can use errorP to promote the Either return value to an ErrorT monad transformer.

Including input length

Like the functions above, but these also provide information about the length of input consumed in order to fully parse each value.

parseL

Arguments

:: (Monad m, ParserInput a)

=> Parser a b

Attoparsec parser

-> Parser a m (Maybe (Either ParsingError (Int, b)))

Pipes parser

Like parse, but also returns the length of input consumed to parse the value.

parsedL

Arguments

:: (Monad m, ParserInput a)

=> Parser a b

Attoparsec parser

-> Producer a m r

Raw input

-> Producer (Int, b) m (Either (ParsingError, Producer a m r) r)

Like parsed, except this tags each parsed value with the length of input consumed to parse the value.

Utils

isEndOfParserInput :: (Monad m, ParserInput a) => Parser a m Bool

Like isEndOfInput, except that it also consumes and discards leading empty chunks.

Types

class (Eq a, Monoid a) => ParserInput a

A class for valid attoparsec input types

Instances

ParserInput ByteString

Strict ByteString.

ParserInput Text

Strict Text.

data ParsingError

A parsing error report, as provided by Attoparsec's Fail.

Constructors

ParsingError

Fields

peContexts :: [String]

Contexts where the parsing error occurred.

peMessage :: String

Parsing error description message.

Instances

Eq ParsingError

Data ParsingError

Read ParsingError

Show ParsingError

Typeable ParsingError

Error ParsingError

Exception ParsingError

Error (ParsingError, Producer a m r)

This instance allows using errorP with parsed and parsedL