    {-# LANGUAGE BangPatterns, CPP, FlexibleInstances, TypeFamilies,
        TypeSynonymInstances, GADTs #-}
    #if __GLASGOW_HASKELL__ >= 702
    {-# LANGUAGE Trustworthy #-} -- Imports internal modules
    #endif
    {-# OPTIONS_GHC -fno-warn-orphans -fno-warn-warnings-deprecations #-}

    -- |
    -- Module      :  Data.Attoparsec.ByteString.Char8
    -- Copyright   :  Bryan O'Sullivan 2007-2015
    -- License     :  BSD3
    --
    -- Maintainer  :  bos@serpentine.com
    -- Stability   :  experimental
    -- Portability :  unknown
    --
    -- Simple, efficient, character-oriented combinator parsing for
    -- 'B.ByteString' strings, loosely based on the Parsec library.

    module Data.Attoparsec.ByteString.Char8
        (
        -- * Character encodings
        -- $encodings

        -- * Parser types
          Parser
        , A.Result
        , A.IResult(..)
        , I.compareResults

        -- * Running parsers
        , A.parse
        , A.feed
        , A.parseOnly
        , A.parseWith
        , A.parseTest

        -- ** Result conversion
        , A.maybeResult
        , A.eitherResult

        -- * Parsing individual characters
        , char
        , char8
        , anyChar
        , notChar
        , satisfy

        -- ** Lookahead
        , peekChar
        , peekChar'

        -- ** Special character parsers
        , digit
        , letter_iso8859_15
        , letter_ascii
        , space

        -- ** Fast predicates
        , isDigit
        , isDigit_w8
        , isAlpha_iso8859_15
        , isAlpha_ascii
        , isSpace
        , isSpace_w8

        -- *** Character classes
        , inClass
        , notInClass

        -- * Efficient string handling
        , I.string
        , I.stringCI
        , skipSpace
        , skipWhile
        , I.take
        , scan
        , takeWhile
        , takeWhile1
        , takeTill

        -- ** String combinators
        -- $specalt
        , (.*>)
        , (<*.)

        -- ** Consume all remaining input
        , I.takeByteString
        , I.takeLazyByteString

        -- * Text parsing
        , I.endOfLine
        , isEndOfLine
        , isHorizontalSpace

        -- * Numeric parsers
        , decimal
        , hexadecimal
        , signed
        , double
        , Number(..)
        , number
        , rational
        , scientific

        -- * Combinators
        , try
        , (<?>)
        , choice
        , count
        , option
        , many'
        , many1
        , many1'
        , manyTill
        , manyTill'
        , sepBy
        , sepBy'
        , sepBy1
        , sepBy1'
        , skipMany
        , skipMany1
        , eitherP
        , I.match
        -- * State observation and manipulation functions
        , I.endOfInput
        , I.atEnd
        ) where

    #if !MIN_VERSION_base(4,8,0)
    import Control.Applicative (pure, (*>), (<*), (<$>))
    import Data.Word (Word)
    #endif
    import Control.Applicative ((<|>))
    import Control.Monad (void, when)
    import Data.Attoparsec.ByteString.FastSet (charClass, memberChar)
    import Data.Attoparsec.ByteString.Internal (Parser)
    import Data.Attoparsec.Combinator
    import Data.Attoparsec.Number (Number(..))
    import Data.Bits (Bits, (.|.), shiftL)
    import Data.ByteString.Internal (c2w, w2c)
    import Data.Int (Int8, Int16, Int32, Int64)
    import Data.String (IsString(..))
    import Data.Scientific (Scientific)
    import qualified Data.Scientific as Sci
    import Data.Word (Word8, Word16, Word32, Word64)
    import Prelude hiding (takeWhile)
    import qualified Data.Attoparsec.ByteString as A
    import qualified Data.Attoparsec.ByteString.Internal as I
    import qualified Data.Attoparsec.Internal as I
    import qualified Data.ByteString as B8
    import qualified Data.ByteString.Char8 as B

    instance (a ~ B.ByteString) => IsString (Parser a) where
        fromString :: String -> Parser a
    fromString = ByteString -> Parser a
    ByteString -> Parser ByteString
    I.string (ByteString -> Parser a)
    -> (String -> ByteString) -> String -> Parser a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . String -> ByteString
    B.pack

    -- $encodings
    --
    -- This module is intended for parsing text that is
    -- represented using an 8-bit character set, e.g. ASCII or
    -- ISO-8859-15.  It /does not/ make any attempt to deal with character
    -- encodings, multibyte characters, or wide characters.  In
    -- particular, all attempts to use characters above code point U+00FF
    -- will give wrong answers.
    --
    -- Code points below U+0100 are simply translated to and from their
    -- numeric values, so e.g. the code point U+00A4 becomes the byte
    -- @0xA4@ (which is the Euro symbol in ISO-8859-15, but the generic
    -- currency sign in ISO-8859-1).  Haskell 'Char' values above U+00FF
    -- are truncated, so e.g. U+1D6B7 is truncated to the byte @0xB7@.

    -- | Consume input as long as the predicate returns 'True', and return
    -- the consumed input.
    --
    -- This parser requires the predicate to succeed on at least one byte
    -- of input: it will fail if the predicate never returns 'True' or if
    -- there is no input left.
    takeWhile1 :: (Char -> Bool) -> Parser B.ByteString
    takeWhile1 :: (Char -> Bool) -> Parser ByteString
    takeWhile1 Char -> Bool
    p = (Word8 -> Bool) -> Parser ByteString
    I.takeWhile1 (Char -> Bool
    p (Char -> Bool) -> (Word8 -> Char) -> Word8 -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Word8 -> Char
    w2c)
    {-# INLINE takeWhile1 #-}

    -- | The parser @satisfy p@ succeeds for any byte for which the
    -- predicate @p@ returns 'True'. Returns the byte that is actually
    -- parsed.
    --
    -- >digit = satisfy isDigit
    -- >    where isDigit c = c >= '0' && c <= '9'
    satisfy :: (Char -> Bool) -> Parser Char
    satisfy :: (Char -> Bool) -> Parser Char
    satisfy = (Word8 -> Char) -> (Char -> Bool) -> Parser Char
    forall a. (Word8 -> a) -> (a -> Bool) -> Parser a
    I.satisfyWith Word8 -> Char
    w2c
    {-# INLINE satisfy #-}

    -- | Match a letter, in the ISO-8859-15 encoding.
    letter_iso8859_15 :: Parser Char
    letter_iso8859_15 :: Parser Char
    letter_iso8859_15 = (Char -> Bool) -> Parser Char
    satisfy Char -> Bool
    isAlpha_iso8859_15 Parser Char -> String -> Parser Char
    forall i a. Parser i a -> String -> Parser i a
    <?> String
    "letter_iso8859_15"
    {-# INLINE letter_iso8859_15 #-}

    -- | Match a letter, in the ASCII encoding.
    letter_ascii :: Parser Char
    letter_ascii :: Parser Char
    letter_ascii = (Char -> Bool) -> Parser Char
    satisfy Char -> Bool
    isAlpha_ascii Parser Char -> String -> Parser Char
    forall i a. Parser i a -> String -> Parser i a
    <?> String
    "letter_ascii"
    {-# INLINE letter_ascii #-}

    -- | A fast alphabetic predicate for the ISO-8859-15 encoding
    --
    -- /Note/: For all character encodings other than ISO-8859-15, and
    -- almost all Unicode code points above U+00A3, this predicate gives
    -- /wrong answers/.
    isAlpha_iso8859_15 :: Char -> Bool
    isAlpha_iso8859_15 :: Char -> Bool
    isAlpha_iso8859_15 Char
    c = (Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Char
    'a' Bool -> Bool -> Bool
    && Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    'z') Bool -> Bool -> Bool
    || (Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Char
    'A' Bool -> Bool -> Bool
    && Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    'Z') Bool -> Bool -> Bool
    ||
                           (Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Char
    '\166' Bool -> Bool -> Bool
    && Char -> Bool
    moby Char
    c)
      where moby :: Char -> Bool
    moby = String -> Char -> Bool
    notInClass String
    "\167\169\171-\179\182\183\185\187\191\215\247"
            {-# NOINLINE moby #-}
    {-# INLINE isAlpha_iso8859_15 #-}

    -- | A fast alphabetic predicate for the ASCII encoding
    --
    -- /Note/: For all character encodings other than ASCII, and
    -- almost all Unicode code points above U+007F, this predicate gives
    -- /wrong answers/.
    isAlpha_ascii :: Char -> Bool
    isAlpha_ascii :: Char -> Bool
    isAlpha_ascii Char
    c = (Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Char
    'a' Bool -> Bool -> Bool
    && Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    'z') Bool -> Bool -> Bool
    || (Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Char
    'A' Bool -> Bool -> Bool
    && Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    'Z')
    {-# INLINE isAlpha_ascii #-}

    -- | Parse a single digit.
    digit :: Parser Char
    digit :: Parser Char
    digit = (Char -> Bool) -> Parser Char
    satisfy Char -> Bool
    isDigit Parser Char -> String -> Parser Char
    forall i a. Parser i a -> String -> Parser i a
    <?> String
    "digit"
    {-# INLINE digit #-}

    -- | A fast digit predicate.
    isDigit :: Char -> Bool
    isDigit :: Char -> Bool
    isDigit Char
    c = Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Char
    '0' Bool -> Bool -> Bool
    && Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    '9'
    {-# INLINE isDigit #-}

    -- | A fast digit predicate.
    isDigit_w8 :: Word8 -> Bool
    isDigit_w8 :: Word8 -> Bool
    isDigit_w8 Word8
    w = Word8
    w Word8 -> Word8 -> Word8
    forall a. Num a => a -> a -> a
    - Word8
    48 Word8 -> Word8 -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Word8
    9
    {-# INLINE isDigit_w8 #-}

    -- | Match any character.
    anyChar :: Parser Char
    anyChar :: Parser Char
    anyChar = (Char -> Bool) -> Parser Char
    satisfy ((Char -> Bool) -> Parser Char) -> (Char -> Bool) -> Parser Char
    forall a b. (a -> b) -> a -> b
    $ Bool -> Char -> Bool
    forall a b. a -> b -> a
    const Bool
    True
    {-# INLINE anyChar #-}

    -- | Match any character, to perform lookahead. Returns 'Nothing' if
    -- end of input has been reached. Does not consume any input.
    --
    -- /Note/: Because this parser does not fail, do not use it with
    -- combinators such as 'many', because such parsers loop until a
    -- failure occurs.  Careless use will thus result in an infinite loop.
    peekChar :: Parser (Maybe Char)
    peekChar :: Parser (Maybe Char)
    peekChar = ((Word8 -> Char) -> Maybe Word8 -> Maybe Char
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap Word8 -> Char
    w2c) (Maybe Word8 -> Maybe Char)
    -> Parser ByteString (Maybe Word8) -> Parser (Maybe Char)
    forall a b. (a -> b) -> Parser ByteString a -> Parser ByteString b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    `fmap` Parser ByteString (Maybe Word8)
    I.peekWord8
    {-# INLINE peekChar #-}

    -- | Match any character, to perform lookahead.  Does not consume any
    -- input, but will fail if end of input has been reached.
    peekChar' :: Parser Char
    peekChar' :: Parser Char
    peekChar' = Word8 -> Char
    w2c (Word8 -> Char) -> Parser ByteString Word8 -> Parser Char
    forall a b. (a -> b) -> Parser ByteString a -> Parser ByteString b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    `fmap` Parser ByteString Word8
    I.peekWord8'
    {-# INLINE peekChar' #-}

    -- | Fast predicate for matching ASCII space characters.
    --
    -- /Note/: This predicate only gives correct answers for the ASCII
    -- encoding.  For instance, it does not recognise U+00A0 (non-breaking
    -- space) as a space character, even though it is a valid ISO-8859-15
    -- byte. For a Unicode-aware and only slightly slower predicate,
    -- use 'Data.Char.isSpace'
    isSpace :: Char -> Bool
    isSpace :: Char -> Bool
    isSpace Char
    c = (Char
    c Char -> Char -> Bool
    forall a. Eq a => a -> a -> Bool
    == Char
    ' ') Bool -> Bool -> Bool
    || (Char
    '\t' Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    c Bool -> Bool -> Bool
    && Char
    c Char -> Char -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Char
    '\r')
    {-# INLINE isSpace #-}

    -- | Fast 'Word8' predicate for matching ASCII space characters.
    isSpace_w8 :: Word8 -> Bool
    isSpace_w8 :: Word8 -> Bool
    isSpace_w8 Word8
    w = Word8
    w Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    32 Bool -> Bool -> Bool
    || Word8
    w Word8 -> Word8 -> Word8
    forall a. Num a => a -> a -> a
    - Word8
    9 Word8 -> Word8 -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Word8
    4
    {-# INLINE isSpace_w8 #-}

    -- | Parse a space character.
    --
    -- /Note/: This parser only gives correct answers for the ASCII
    -- encoding.  For instance, it does not recognise U+00A0 (non-breaking
    -- space) as a space character, even though it is a valid ISO-8859-15
    -- byte.
    space :: Parser Char
    space :: Parser Char
    space = (Char -> Bool) -> Parser Char
    satisfy Char -> Bool
    isSpace Parser Char -> String -> Parser Char
    forall i a. Parser i a -> String -> Parser i a
    <?> String
    "space"
    {-# INLINE space #-}

    -- | Match a specific character.
    char :: Char -> Parser Char
    char :: Char -> Parser Char
    char Char
    c = (Char -> Bool) -> Parser Char
    satisfy (Char -> Char -> Bool
    forall a. Eq a => a -> a -> Bool
    == Char
    c) Parser Char -> String -> Parser Char
    forall i a. Parser i a -> String -> Parser i a
    <?> [Char
    c]
    {-# INLINE char #-}

    -- | Match a specific character, but return its 'Word8' value.
    char8 :: Char -> Parser Word8
    char8 :: Char -> Parser ByteString Word8
    char8 Char
    c = (Word8 -> Bool) -> Parser ByteString Word8
    I.satisfy (Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Char -> Word8
    c2w Char
    c) Parser ByteString Word8 -> String -> Parser ByteString Word8
    forall i a. Parser i a -> String -> Parser i a
    <?> [Char
    c]
    {-# INLINE char8 #-}

    -- | Match any character except the given one.
    notChar :: Char -> Parser Char
    notChar :: Char -> Parser Char
    notChar Char
    c = (Char -> Bool) -> Parser Char
    satisfy (Char -> Char -> Bool
    forall a. Eq a => a -> a -> Bool
    /= Char
    c) Parser Char -> String -> Parser Char
    forall i a. Parser i a -> String -> Parser i a
    <?> String
    "not " String -> String -> String
    forall a. [a] -> [a] -> [a]
    ++ [Char
    c]
    {-# INLINE notChar #-}

    -- | Match any character in a set.
    --
    -- >vowel = inClass "aeiou"
    --
    -- Range notation is supported.
    --
    -- >halfAlphabet = inClass "a-nA-N"
    --
    -- To add a literal \'-\' to a set, place it at the beginning or end
    -- of the string.
    inClass :: String -> Char -> Bool
    inClass :: String -> Char -> Bool
    inClass String
    s = (Char -> FastSet -> Bool
    `memberChar` FastSet
    mySet)
        where mySet :: FastSet
    mySet = String -> FastSet
    charClass String
    s
    {-# INLINE inClass #-}

    -- | Match any character not in a set.
    notInClass :: String -> Char -> Bool
    notInClass :: String -> Char -> Bool
    notInClass String
    s = Bool -> Bool
    not (Bool -> Bool) -> (Char -> Bool) -> Char -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . String -> Char -> Bool
    inClass String
    s
    {-# INLINE notInClass #-}

    -- | Consume input as long as the predicate returns 'True', and return
    -- the consumed input.
    --
    -- This parser does not fail.  It will return an empty string if the
    -- predicate returns 'False' on the first byte of input.
    --
    -- /Note/: Because this parser does not fail, do not use it with
    -- combinators such as 'many', because such parsers loop until a
    -- failure occurs.  Careless use will thus result in an infinite loop.
    takeWhile :: (Char -> Bool) -> Parser B.ByteString
    takeWhile :: (Char -> Bool) -> Parser ByteString
    takeWhile Char -> Bool
    p = (Word8 -> Bool) -> Parser ByteString
    I.takeWhile (Char -> Bool
    p (Char -> Bool) -> (Word8 -> Char) -> Word8 -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Word8 -> Char
    w2c)
    {-# INLINE takeWhile #-}

    -- | A stateful scanner.  The predicate consumes and transforms a
    -- state argument, and each transformed state is passed to successive
    -- invocations of the predicate on each byte of the input until one
    -- returns 'Nothing' or the input ends.
    --
    -- This parser does not fail.  It will return an empty string if the
    -- predicate returns 'Nothing' on the first byte of input.
    --
    -- /Note/: Because this parser does not fail, do not use it with
    -- combinators such as 'many', because such parsers loop until a
    -- failure occurs.  Careless use will thus result in an infinite loop.
    scan :: s -> (s -> Char -> Maybe s) -> Parser B.ByteString
    scan :: forall s. s -> (s -> Char -> Maybe s) -> Parser ByteString
    scan s
    s0 s -> Char -> Maybe s
    p = s -> (s -> Word8 -> Maybe s) -> Parser ByteString
    forall s. s -> (s -> Word8 -> Maybe s) -> Parser ByteString
    I.scan s
    s0 (\s
    s -> s -> Char -> Maybe s
    p s
    s (Char -> Maybe s) -> (Word8 -> Char) -> Word8 -> Maybe s
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Word8 -> Char
    w2c)
    {-# INLINE scan #-}

    -- | Consume input as long as the predicate returns 'False'
    -- (i.e. until it returns 'True'), and return the consumed input.
    --
    -- This parser does not fail.  It will return an empty string if the
    -- predicate returns 'True' on the first byte of input.
    --
    -- /Note/: Because this parser does not fail, do not use it with
    -- combinators such as 'many', because such parsers loop until a
    -- failure occurs.  Careless use will thus result in an infinite loop.
    takeTill :: (Char -> Bool) -> Parser B.ByteString
    takeTill :: (Char -> Bool) -> Parser ByteString
    takeTill Char -> Bool
    p = (Word8 -> Bool) -> Parser ByteString
    I.takeTill (Char -> Bool
    p (Char -> Bool) -> (Word8 -> Char) -> Word8 -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Word8 -> Char
    w2c)
    {-# INLINE takeTill #-}

    -- | Skip past input for as long as the predicate returns 'True'.
    skipWhile :: (Char -> Bool) -> Parser ()
    skipWhile :: (Char -> Bool) -> Parser ()
    skipWhile Char -> Bool
    p = (Word8 -> Bool) -> Parser ()
    I.skipWhile (Char -> Bool
    p (Char -> Bool) -> (Word8 -> Char) -> Word8 -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Word8 -> Char
    w2c)
    {-# INLINE skipWhile #-}

    -- | Skip over white space.
    skipSpace :: Parser ()
    skipSpace :: Parser ()
    skipSpace = (Word8 -> Bool) -> Parser ()
    I.skipWhile Word8 -> Bool
    isSpace_w8
    {-# INLINE skipSpace #-}

    -- $specalt
    --
    -- If you enable the @OverloadedStrings@ language extension, you can
    -- use the '*>' and '<*' combinators to simplify the common task of
    -- matching a statically known string, then immediately parsing
    -- something else.
    --
    -- Instead of writing something like this:
    --
    -- @
    --'I.string' \"foo\" '*>' wibble
    -- @
    --
    -- Using @OverloadedStrings@, you can omit the explicit use of
    -- 'I.string', and write a more compact version:
    --
    -- @
    -- \"foo\" '*>' wibble
    -- @
    --
    -- (Note: the '.*>' and '<*.' combinators that were originally
    -- provided for this purpose are obsolete and unnecessary, and will be
    -- removed in the next major version.)

    -- | /Obsolete/. A type-specialized version of '*>' for
    -- 'B.ByteString'. Use '*>' instead.
    (.*>) :: B.ByteString -> Parser a -> Parser a
    ByteString
    s .*> :: forall a. ByteString -> Parser a -> Parser a
    .*> Parser a
    f = ByteString -> Parser ByteString
    I.string ByteString
    s Parser ByteString -> Parser a -> Parser a
    forall a b.
    Parser ByteString a -> Parser ByteString b -> Parser ByteString b
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> Parser a
    f
    {-# DEPRECATED (.*>) "This is no longer necessary, and will be removed. Use '*>' instead." #-}

    -- | /Obsolete/. A type-specialized version of '<*' for
    -- 'B.ByteString'. Use '<*' instead.
    (<*.) :: Parser a -> B.ByteString -> Parser a
    Parser a
    f <*. :: forall a. Parser a -> ByteString -> Parser a
    <*. ByteString
    s = Parser a
    f Parser a -> Parser ByteString -> Parser a
    forall a b.
    Parser ByteString a -> Parser ByteString b -> Parser ByteString a
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f a
    <* ByteString -> Parser ByteString
    I.string ByteString
    s
    {-# DEPRECATED (<*.) "This is no longer necessary, and will be removed. Use '<*' instead." #-}

    -- | A predicate that matches either a carriage return @\'\\r\'@ or
    -- newline @\'\\n\'@ character.
    isEndOfLine :: Word8 -> Bool
    isEndOfLine :: Word8 -> Bool
    isEndOfLine Word8
    w = Word8
    w Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    13 Bool -> Bool -> Bool
    || Word8
    w Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    10
    {-# INLINE isEndOfLine #-}

    -- | A predicate that matches either a space @\' \'@ or horizontal tab
    -- @\'\\t\'@ character.
    isHorizontalSpace :: Word8 -> Bool
    isHorizontalSpace :: Word8 -> Bool
    isHorizontalSpace Word8
    w = Word8
    w Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    32 Bool -> Bool -> Bool
    || Word8
    w Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    9
    {-# INLINE isHorizontalSpace #-}

    -- | Parse and decode an unsigned hexadecimal number.  The hex digits
    -- @\'a\'@ through @\'f\'@ may be upper or lower case.
    --
    -- This parser does not accept a leading @\"0x\"@ string.
    hexadecimal :: (Integral a, Bits a) => Parser a
    hexadecimal :: forall a. (Integral a, Bits a) => Parser a
    hexadecimal = (a -> Word8 -> a) -> a -> ByteString -> a
    forall a. (a -> Word8 -> a) -> a -> ByteString -> a
    B8.foldl' a -> Word8 -> a
    forall {a} {a}. (Bits a, Integral a, Num a) => a -> a -> a
    step a
    0 (ByteString -> a) -> Parser ByteString -> Parser ByteString a
    forall a b. (a -> b) -> Parser ByteString a -> Parser ByteString b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    `fmap` (Word8 -> Bool) -> Parser ByteString
    I.takeWhile1 Word8 -> Bool
    forall {a}. (Ord a, Num a) => a -> Bool
    isHexDigit
      where
        isHexDigit :: a -> Bool
    isHexDigit a
    w = (a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    >= a
    48 Bool -> Bool -> Bool
    && a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    <= a
    57) Bool -> Bool -> Bool
    ||
                       (a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    >= a
    97 Bool -> Bool -> Bool
    && a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    <= a
    102) Bool -> Bool -> Bool
    ||
                       (a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    >= a
    65 Bool -> Bool -> Bool
    && a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    <= a
    70)
        step :: a -> a -> a
    step a
    a a
    w | a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    >= a
    48 Bool -> Bool -> Bool
    && a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    <= a
    57  = (a
    a a -> Int -> a
    forall a. Bits a => a -> Int -> a
    `shiftL` Int
    4) a -> a -> a
    forall a. Bits a => a -> a -> a
    .|. a -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (a
    w a -> a -> a
    forall a. Num a => a -> a -> a
    - a
    48)
                 | a
    w a -> a -> Bool
    forall a. Ord a => a -> a -> Bool
    >= a
    97             = (a
    a a -> Int -> a
    forall a. Bits a => a -> Int -> a
    `shiftL` Int
    4) a -> a -> a
    forall a. Bits a => a -> a -> a
    .|. a -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (a
    w a -> a -> a
    forall a. Num a => a -> a -> a
    - a
    87)
                 | Bool
    otherwise           = (a
    a a -> Int -> a
    forall a. Bits a => a -> Int -> a
    `shiftL` Int
    4) a -> a -> a
    forall a. Bits a => a -> a -> a
    .|. a -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (a
    w a -> a -> a
    forall a. Num a => a -> a -> a
    - a
    55)
    {-# SPECIALISE hexadecimal :: Parser Int #-}
    {-# SPECIALISE hexadecimal :: Parser Int8 #-}
    {-# SPECIALISE hexadecimal :: Parser Int16 #-}
    {-# SPECIALISE hexadecimal :: Parser Int32 #-}
    {-# SPECIALISE hexadecimal :: Parser Int64 #-}
    {-# SPECIALISE hexadecimal :: Parser Integer #-}
    {-# SPECIALISE hexadecimal :: Parser Word #-}
    {-# SPECIALISE hexadecimal :: Parser Word8 #-}
    {-# SPECIALISE hexadecimal :: Parser Word16 #-}
    {-# SPECIALISE hexadecimal :: Parser Word32 #-}
    {-# SPECIALISE hexadecimal :: Parser Word64 #-}

    -- | Parse and decode an unsigned decimal number.
    decimal :: Integral a => Parser a
    decimal :: forall a. Integral a => Parser a
    decimal = (a -> Word8 -> a) -> a -> ByteString -> a
    forall a. (a -> Word8 -> a) -> a -> ByteString -> a
    B8.foldl' a -> Word8 -> a
    forall {a} {a}. (Integral a, Num a) => a -> a -> a
    step a
    0 (ByteString -> a) -> Parser ByteString -> Parser ByteString a
    forall a b. (a -> b) -> Parser ByteString a -> Parser ByteString b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    `fmap` (Word8 -> Bool) -> Parser ByteString
    I.takeWhile1 Word8 -> Bool
    isDigit_w8
      where step :: a -> a -> a
    step a
    a a
    w = a
    a a -> a -> a
    forall a. Num a => a -> a -> a
    * a
    10 a -> a -> a
    forall a. Num a => a -> a -> a
    + a -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (a
    w a -> a -> a
    forall a. Num a => a -> a -> a
    - a
    48)
    {-# SPECIALISE decimal :: Parser Int #-}
    {-# SPECIALISE decimal :: Parser Int8 #-}
    {-# SPECIALISE decimal :: Parser Int16 #-}
    {-# SPECIALISE decimal :: Parser Int32 #-}
    {-# SPECIALISE decimal :: Parser Int64 #-}
    {-# SPECIALISE decimal :: Parser Integer #-}
    {-# SPECIALISE decimal :: Parser Word #-}
    {-# SPECIALISE decimal :: Parser Word8 #-}
    {-# SPECIALISE decimal :: Parser Word16 #-}
    {-# SPECIALISE decimal :: Parser Word32 #-}
    {-# SPECIALISE decimal :: Parser Word64 #-}

    -- | Parse a number with an optional leading @\'+\'@ or @\'-\'@ sign
    -- character.
    signed :: Num a => Parser a -> Parser a
    {-# SPECIALISE signed :: Parser Int -> Parser Int #-}
    {-# SPECIALISE signed :: Parser Int8 -> Parser Int8 #-}
    {-# SPECIALISE signed :: Parser Int16 -> Parser Int16 #-}
    {-# SPECIALISE signed :: Parser Int32 -> Parser Int32 #-}
    {-# SPECIALISE signed :: Parser Int64 -> Parser Int64 #-}
    {-# SPECIALISE signed :: Parser Integer -> Parser Integer #-}
    signed :: forall a. Num a => Parser a -> Parser a
    signed Parser a
    p = (a -> a
    forall a. Num a => a -> a
    negate (a -> a) -> Parser a -> Parser a
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> (Char -> Parser ByteString Word8
    char8 Char
    '-' Parser ByteString Word8 -> Parser a -> Parser a
    forall a b.
    Parser ByteString a -> Parser ByteString b -> Parser ByteString b
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> Parser a
    p))
           Parser a -> Parser a -> Parser a
    forall a.
    Parser ByteString a -> Parser ByteString a -> Parser ByteString a
    forall (f :: * -> *) a. Alternative f => f a -> f a -> f a
    <|> (Char -> Parser ByteString Word8
    char8 Char
    '+' Parser ByteString Word8 -> Parser a -> Parser a
    forall a b.
    Parser ByteString a -> Parser ByteString b -> Parser ByteString b
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> Parser a
    p)
           Parser a -> Parser a -> Parser a
    forall a.
    Parser ByteString a -> Parser ByteString a -> Parser ByteString a
    forall (f :: * -> *) a. Alternative f => f a -> f a -> f a
    <|> Parser a
    p

    -- | Parse a rational number.
    --
    -- The syntax accepted by this parser is the same as for 'double'.
    --
    -- /Note/: this parser is not safe for use with inputs from untrusted
    -- sources.  An input with a suitably large exponent such as
    -- @"1e1000000000"@ will cause a huge 'Integer' to be allocated,
    -- resulting in what is effectively a denial-of-service attack.
    --
    -- In most cases, it is better to use 'double' or 'scientific'
    -- instead.
    rational :: Fractional a => Parser a
    {-# SPECIALIZE rational :: Parser Double #-}
    {-# SPECIALIZE rational :: Parser Float #-}
    {-# SPECIALIZE rational :: Parser Rational #-}
    {-# SPECIALIZE rational :: Parser Scientific #-}
    rational :: forall a. Fractional a => Parser a
    rational = (Scientific -> a) -> Parser a
    forall a. (Scientific -> a) -> Parser a
    scientifically Scientific -> a
    forall a b. (Real a, Fractional b) => a -> b
    realToFrac

    -- | Parse a 'Double'.
    --
    -- This parser accepts an optional leading sign character, followed by
    -- at most one decimal digit.  The syntax is similar to that accepted by
    -- the 'read' function, with the exception that a trailing @\'.\'@ is
    -- consumed.
    --
    -- === Examples
    --
    -- These examples use this helper:
    --
    -- @
    -- r :: 'Parser' a -> 'Data.ByteString.ByteString' -> 'Data.Attoparsec.ByteString.Result' a
    -- r p s = 'feed' ('Data.Attoparsec.parse' p s) 'mempty'
    -- @
    --
    -- Examples with behaviour identical to 'read', if you feed an empty
    -- continuation to the first result:
    --
    -- > double "3"     == Done "" 3.0
    -- > double "3.1"   == Done "" 3.1
    -- > double "3e4"   == Done "" 30000.0
    -- > double "3.1e4" == Done "" 31000.0
    -- > double "3e"    == Done "e" 3.0
    --
    -- Examples with behaviour identical to 'read':
    --
    -- > double ".3"    == Fail ".3" _ _
    -- > double "e3"    == Fail "e3" _ _
    --
    -- Example of difference from 'read':
    --
    -- > double "3.foo" == Done "foo" 3.0
    --
    -- This function does not accept string representations of \"NaN\" or
    -- \"Infinity\".
    double :: Parser Double
    double :: Parser Double
    double = (Scientific -> Double) -> Parser Double
    forall a. (Scientific -> a) -> Parser a
    scientifically Scientific -> Double
    forall a. RealFloat a => Scientific -> a
    Sci.toRealFloat

    -- | Parse a number, attempting to preserve both speed and precision.
    --
    -- The syntax accepted by this parser is the same as for 'double'.
    number :: Parser Number
    number :: Parser Number
    number = (Scientific -> Number) -> Parser Number
    forall a. (Scientific -> a) -> Parser a
    scientifically ((Scientific -> Number) -> Parser Number)
    -> (Scientific -> Number) -> Parser Number
    forall a b. (a -> b) -> a -> b
    $ \Scientific
    s ->
                let e :: Int
    e = Scientific -> Int
    Sci.base10Exponent Scientific
    s
                    c :: Integer
    c = Scientific -> Integer
    Sci.coefficient Scientific
    s
                in if Int
    e Int -> Int -> Bool
    forall a. Ord a => a -> a -> Bool
    >= Int
    0
                   then Integer -> Number
    I (Integer
    c Integer -> Integer -> Integer
    forall a. Num a => a -> a -> a
    * Integer
    10 Integer -> Int -> Integer
    forall a b. (Num a, Integral b) => a -> b -> a
    ^ Int
    e)
                   else Double -> Number
    D (Scientific -> Double
    forall a. RealFloat a => Scientific -> a
    Sci.toRealFloat Scientific
    s)
    {-# DEPRECATED number "Use 'scientific' instead." #-}

    -- | Parse a scientific number.
    --
    -- The syntax accepted by this parser is the same as for 'double'.
    scientific :: Parser Scientific
    scientific :: Parser Scientific
    scientific = (Scientific -> Scientific) -> Parser Scientific
    forall a. (Scientific -> a) -> Parser a
    scientifically Scientific -> Scientific
    forall a. a -> a
    id

    -- A strict pair
    data SP = SP !Integer {-# UNPACK #-}!Int

    {-# INLINE scientifically #-}
    scientifically :: (Scientific -> a) -> Parser a
    scientifically :: forall a. (Scientific -> a) -> Parser a
    scientifically Scientific -> a
    h = do
      let minus :: Word8
    minus = Word8
    45
          plus :: Word8
    plus  = Word8
    43
      sign <- Parser ByteString Word8
    I.peekWord8'
      let !positive = Word8
    sign Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    plus Bool -> Bool -> Bool
    || Word8
    sign Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    /= Word8
    minus
      when (sign == plus || sign == minus) $
        void $ I.anyWord8

      n <- decimal

      let f ByteString
    fracDigits = Integer -> Int -> SP
    SP ((Integer -> Word8 -> Integer) -> Integer -> ByteString -> Integer
    forall a. (a -> Word8 -> a) -> a -> ByteString -> a
    B8.foldl' Integer -> Word8 -> Integer
    forall {a} {a}. (Integral a, Num a) => a -> a -> a
    step Integer
    n ByteString
    fracDigits)
                            (Int -> Int
    forall a. Num a => a -> a
    negate (Int -> Int) -> Int -> Int
    forall a b. (a -> b) -> a -> b
    $ ByteString -> Int
    B8.length ByteString
    fracDigits)
          step a
    a a
    w = a
    a a -> a -> a
    forall a. Num a => a -> a -> a
    * a
    10 a -> a -> a
    forall a. Num a => a -> a -> a
    + a -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (a
    w a -> a -> a
    forall a. Num a => a -> a -> a
    - a
    48)

      dotty <- I.peekWord8
      -- '.' -> ascii 46
      SP c e <- case dotty of
                  Just Word8
    46 -> Parser ByteString Word8
    I.anyWord8 Parser ByteString Word8
    -> Parser ByteString SP -> Parser ByteString SP
    forall a b.
    Parser ByteString a -> Parser ByteString b -> Parser ByteString b
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> (ByteString -> SP
    f (ByteString -> SP) -> Parser ByteString -> Parser ByteString SP
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> (Word8 -> Bool) -> Parser ByteString
    I.takeWhile Word8 -> Bool
    isDigit_w8)
                  Maybe Word8
    _       -> SP -> Parser ByteString SP
    forall a. a -> Parser ByteString a
    forall (f :: * -> *) a. Applicative f => a -> f a
    pure (Integer -> Int -> SP
    SP Integer
    n Int
    0)

      let !signedCoeff | Bool
    positive  =  Integer
    c
                       | Bool
    otherwise = -Integer
    c

      let littleE = Word8
    101
          bigE    = Word8
    69
      (I.satisfy (\Word8
    ex -> Word8
    ex Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    littleE Bool -> Bool -> Bool
    || Word8
    ex Word8 -> Word8 -> Bool
    forall a. Eq a => a -> a -> Bool
    == Word8
    bigE) *>
          fmap (h . Sci.scientific signedCoeff . (e +)) (signed decimal)) <|>
        return (h $ Sci.scientific signedCoeff    e)