Data.Attoparsec.Internal.Types

attoparsec-0.13.0.1: Fast combinator parsing for bytestrings and text

Copyright | Bryan O'Sullivan 2007-2015
License | BSD3
Maintainer | bos@serpentine.com
Stability | experimental
Portability | unknown
Safe Haskell | None
Language | Haskell98

Data.Attoparsec.Internal.Types

Description

Simple, efficient parser combinators, loosely based on the Parsec library.

Synopsis

- newtype Parser i a = Parser {
  - runParser :: forall r. State i -> Pos -> More -> Failure i (State i) r -> Success i (State i) a r -> IResult i r
  }
- type family State i
- type Failure i t r = t -> Pos -> More -> [String] -> String -> IResult i r
- type Success i t a r = t -> Pos -> More -> a -> IResult i r
- newtype Pos = Pos {
  - fromPos :: Int
  }
- data IResult i r
  - = Fail i [String] String
  - | Partial (i -> IResult i r)
  - | Done i r
- data More
  - = Complete
  - | Incomplete
- (<>) :: Monoid m => m -> m -> m
- class Monoid c => Chunk c where
  - type ChunkElem c
  - nullChunk :: c -> Bool
  - pappendChunk :: State c -> c -> State c
  - atBufferEnd :: c -> State c -> Pos
  - bufferElemAt :: c -> Pos -> State c -> Maybe (ChunkElem c, Int)
  - chunkElemToChar :: c -> ChunkElem c -> Char

# Documentation

newtype Parser i a

The core parser type. This is parameterised over the type `i` of string being processed.

This type is an instance of the following classes:

- `Monad`, where `fail` throws an exception (i.e. fails) with an error message.
- `Functor` and `Applicative`, which follow the usual definitions.
- `MonadPlus`, where `mzero` fails (with no error message) and `mplus` executes the right-hand parser if the left-hand one fails. When the parser on the right executes, the input is reset to the same state as the parser on the left started with. (In other words, attoparsec is a backtracking parser that supports arbitrary lookahead.)
- `Alternative`, which follows `MonadPlus`.

Constructors

Parser |
Fields runParser :: forall r. State i -> Pos -> More -> Failure i (State i) r -> Success i (State i) a r -> IResult i r

Instances

Monad (Parser i) |
Functor (Parser i) |
Applicative (Parser i) |
Alternative (Parser i) |
MonadPlus (Parser i) |
Monoid (Parser i a) |

type family State i

Instances

type State ByteString |
type State Text |

type Failure i t r = t -> Pos -> More -> [String] -> String -> IResult i r

type Success i t a r = t -> Pos -> More -> a -> IResult i r

newtype Pos

Constructors

Pos |
Fields fromPos :: Int

Instances

Eq Pos |
Num Pos |
Ord Pos |
Show Pos |

data IResult i r

The result of a parse. This is parameterised over the type `i` of string that was processed.

This type is an instance of `Functor`, where `fmap` transforms the value in a `Done` result.

Constructors

Fail i [String] String | The parse failed. The `i` parameter is the input that had not yet been consumed when the failure occurred. The `[``String``]` is a list of contexts in which the error occurred. The `String` is the message describing the error, if any.
Partial (i -> IResult i r) | Supply this continuation with more input so that the parser can resume. To indicate that no more input is available, pass an empty string to the continuation. Note: if you get a `Partial` result, do not call its continuation more than once.
Done i r | The parse succeeded. The `i` parameter is the input that had not yet been consumed (if any) when the parse succeeded.

Instances

Functor (IResult i) |
(Show i, Show r) => Show (IResult i r) |
(NFData i, NFData r) => NFData (IResult i r) |

data More

Have we read all available input?

Constructors

Complete |
Incomplete |

Instances

Eq More |
Show More |
Monoid More |

(<>) :: Monoid m => m -> m -> m

class Monoid c => Chunk c where

A common interface for input chunks.

Associated Types

type ChunkElem c

Methods

nullChunk :: c -> Bool

Test if the chunk is empty.

pappendChunk :: State c -> c -> State c

Append chunk to a buffer.

atBufferEnd :: c -> State c -> Pos

Position at the end of a buffer. The first argument is ignored.

bufferElemAt :: c -> Pos -> State c -> Maybe (ChunkElem c, Int)

Return the buffer element at the given position along with its length.

chunkElemToChar :: c -> ChunkElem c -> Char

Map an element to the corresponding character. The first argument is ignored.

Instances

Chunk ByteString |
Chunk Text |