Data.Deserializer

Deserialize an unsigned 16-bit integer in host byte order.

Deserialize an unsigned 32-bit integer in host byte order.

Deserialize an unsigned 64-bit integer in host byte order.

Deserialize an unsigned native-sized integer in serializer default byte order.

Deserialize an unsigned native-sized integer in little endian.

Deserialize an unsigned native-sized integer in big endian.

Deserialize an unsigned native-sized integer in host byte order.

Deserialize a signed 8-bit integer.

Deserialize a signed 16-bit integer in serializer default byte order.

Deserialize a signed 16-bit integer in little endian.

Deserialize a signed 16-bit integer in big endian.

Deserialize a signed 16-bit integer in host byte order.

Deserialize a signed 32-bit integer in serializer default byte order.

Deserialize a signed 32-bit integer in little endian.

Deserialize a signed 32-bit integer in big endian.

Deserialize a signed 32-bit integer in host byte order.

Deserialize a signed 64-bit integer in serializer default byte order.

Deserialize a signed 64-bit integer in little endian.

Deserialize a signed 64-bit integer in big endian.

Deserialize a signed 64-bit integer in host byte order.

Deserialize a signed native-sized integer in serializer default byte order.

Deserialize a signed native-sized integer in little endian.

Deserialize a signed native-sized integer in big endian.

Deserialize a signed native-sized integer in host byte order.

Additional functionality needed to describe parsers independent of input type.

count n p parses n occurrences of p. If n is smaller or equal to zero, the parser equals to return []. Returns a list of n values returned by p.

Zero or more.

Examples

>>> many (putStr "la")lalalalalalalalala... * goes on forever *

>>> many NothingJust []

>>> take 5 <$> many (Just 1)* hangs forever *

Note that this function can be used with Parsers based on Applicatives. In that case many parser will attempt to parse parser zero or more times until it fails.

One or more.

Examples

>>> some (putStr "la")lalalalalalalalala... * goes on forever *

>>> some Nothingnothing

>>> take 5 <$> some (Just 1)* hangs forever *

Note that this function can be used with Parsers based on Applicatives. In that case some parser will attempt to parse parser one or more times until it fails.

endBy p sep parses zero or more occurrences of p, separated and ended by sep. Returns a list of values returned by p.

  cStatements  = cStatement `endBy` semi

sepBy p sep parses zero or more occurrences of p, separated by sep. Returns a list of values returned by p.

 commaSep p  = p `sepBy` (symbol ",")

One or none.

It is useful for modelling any computation that is allowed to fail.

Examples

Using the Alternative instance of Control.Monad.Except, the following functions:

>>> import Control.Monad.Except

>>> canFail = throwError "it failed" :: Except String Int>>> final = return 42                :: Except String Int

Can be combined by allowing the first function to fail:

>>> runExcept $ canFail *> finalLeft "it failed"

>>> runExcept $ optional canFail *> finalRight 42

between open close p parses open, followed by p and close. Returns the value returned by p.

 braces  = between (symbol "{") (symbol "}")

chainl p op x parses zero or more occurrences of p, separated by op. Returns a value obtained by a left associative application of all functions returned by op to the values returned by p. If there are zero occurrences of p, the value x is returned.

chainl1 p op x parses one or more occurrences of p, separated by op Returns a value obtained by a left associative application of all functions returned by op to the values returned by p. . This parser can for example be used to eliminate left recursion which typically occurs in expression grammars.

 expr   = term   `chainl1` addop
 term   = factor `chainl1` mulop
 factor = parens expr <|> integer

 mulop  = (*) <$ symbol "*"
      <|> div <$ symbol "/"

 addop  = (+) <$ symbol "+"
      <|> (-) <$ symbol "-"

chainr p op x parses zero or more occurrences of p, separated by op Returns a value obtained by a right associative application of all functions returned by op to the values returned by p. If there are no occurrences of p, the value x is returned.

chainr1 p op x parses one or more occurrences of p, separated by op Returns a value obtained by a right associative application of all functions returned by op to the values returned by p.

choice ps tries to apply the parsers in the list ps in order, until one of them succeeds. Returns the value of the succeeding parser.

endBy1 p sep parses one or more occurrences of p, separated and ended by sep. Returns a list of values returned by p.

endByNonEmpty p sep parses one or more occurrences of p, separated and ended by sep. Returns a non-empty list of values returned by p.

manyTill p end applies parser p zero or more times until parser end succeeds. Returns the list of values returned by p. This parser can be used to scan comments:

 simpleComment   = do{ string "<!--"
                     ; manyTill anyChar (try (string "-->"))
                     }

Note the overlapping parsers anyChar and string "-->", and therefore the use of the try combinator.

option x p tries to apply parser p. If p fails without consuming input, it returns the value x, otherwise the value returned by p.

 priority = option 0 (digitToInt <$> digit)

sepBy1 p sep parses one or more occurrences of p, separated by sep. Returns a list of values returned by p.

sepByNonEmpty p sep parses one or more occurrences of p, separated by sep. Returns a non-empty list of values returned by p.

sepEndBy p sep parses zero or more occurrences of p, separated and optionally ended by sep, ie. haskell style statements. Returns a list of values returned by p.

 haskellStatements  = haskellStatement `sepEndBy` semi

sepEndBy1 p sep parses one or more occurrences of p, separated and optionally ended by sep. Returns a list of values returned by p.

sepEndByNonEmpty p sep parses one or more occurrences of p, separated and optionally ended by sep. Returns a non-empty list of values returned by p.

skipOptional p tries to apply parser p. It will parse p or nothing. It only fails if p fails after consuming input. It discards the result of p. (Plays the role of parsec's optional, which conflicts with Applicative's optional)

p `surroundedBy` f is p surrounded by f. Shortcut for between f f p. As in between, returns the value returned by p.

A shorthand for flip (<?>).

Additional functionality needed to describe parsers independent of input type.

Deserializer wrapper with little endian default byte order.

Deserializer wrapper with big endian default byte order.

Force the default byte order.

Force the default byte order to be the host byte order.

Deserialization result.

Map Deserialized to True and Malformed to False.

Map Deserialized to False and Malformed to True.

Map Deserialized values to Just and Malformed to Nothing.

Deserialize a ByteString via the default deserializer.