Text.ParserCombinators.Poly.ByteString

The Parser datatype

newtype Parser a

This Parser datatype is a specialised parsing monad with error reporting. Whereas the standard version can be used for arbitrary token types, this version is specialised to ByteString input only.

Constructors

P (ByteString -> Result ByteString a)

Instances

Monad Parser

Defined in Text.ParserCombinators.Poly.ByteString

Methods

(>>=) :: Parser a -> (a -> Parser b) -> Parser b

(>>) :: Parser a -> Parser b -> Parser b

return :: a -> Parser a

fail :: String -> Parser a

Functor Parser

Defined in Text.ParserCombinators.Poly.ByteString

Methods

fmap :: (a -> b) -> Parser a -> Parser b

(<$) :: a -> Parser b -> Parser a

MonadFail Parser

Defined in Text.ParserCombinators.Poly.ByteString

Methods

fail :: String -> Parser a

Applicative Parser

Defined in Text.ParserCombinators.Poly.ByteString

Methods

pure :: a -> Parser a

(<*>) :: Parser (a -> b) -> Parser a -> Parser b

liftA2 :: (a -> b -> c) -> Parser a -> Parser b -> Parser c

(*>) :: Parser a -> Parser b -> Parser b

(<*) :: Parser a -> Parser b -> Parser a

Alternative Parser

Defined in Text.ParserCombinators.Poly.ByteString

Methods

empty :: Parser a

(<|>) :: Parser a -> Parser a -> Parser a

some :: Parser a -> Parser [a]

many :: Parser a -> Parser [a]

PolyParse Parser

Defined in Text.ParserCombinators.Poly.ByteString

Commitment Parser

Defined in Text.ParserCombinators.Poly.ByteString

Methods

commit :: Parser a -> Parser a

adjustErr :: Parser a -> (String -> String) -> Parser a

oneOf' :: [(String, Parser a)] -> Parser a

data Result z a

A return type like Either, that distinguishes not only between right and wrong answers, but also has commitment, so that a failure cannot be undone. This should only be used for writing very primitive parsers - really it is an internal detail of the library. The z type is the remaining unconsumed input.

Constructors

Success z a

Failure z String

Committed (Result z a)

Instances

Functor (Result z)

Defined in Text.ParserCombinators.Poly.Result

Methods

fmap :: (a -> b) -> Result z a -> Result z b

(<$) :: a -> Result z b -> Result z a

runParser :: Parser a -> ByteString -> (Either String a, ByteString)

Apply a parser to an input token sequence.

Basic parsers

next :: Parser Word8

Simply return the next token in the input tokenstream.

eof :: Parser ()

Succeed if the end of file/input has been reached, fail otherwise.

satisfy :: (Word8 -> Bool) -> Parser Word8

Return the next token if it satisfies the given predicate.

onFail :: Parser a -> Parser a -> Parser a

p onFail q means parse p, unless p fails, in which case parse q instead. Can be chained together to give multiple attempts to parse something. (Note that q could itself be a failing parser, e.g. to change the error message from that defined in p to something different.) However, a severe failure in p cannot be ignored.

Derived parsers (but implemented more efficiently)

manySatisfy :: (Word8 -> Bool) -> Parser ByteString

manySatisfy p is a more efficient fused version of many (satisfy p)

many1Satisfy :: (Word8 -> Bool) -> Parser ByteString

many1Satisfy p is a more efficient fused version of many1 (satisfy p)

Re-parsing

reparse :: ByteString -> Parser ()

Push some tokens back onto the front of the input stream and reparse. This is useful e.g. for recursively expanding macros. When the user-parser recognises a macro use, it can lookup the macro expansion from the parse state, lex it, and then stuff the lexed expansion back down into the parser.

Re-export all more general combinators

module Text.ParserCombinators.Poly.Base