    -- |
    -- Module      :  Text.Megaparsec.Char.Lexer
    -- Copyright   :  © 2015–present Megaparsec contributors
    --                © 2007 Paolo Martini
    --                © 1999–2001 Daan Leijen
    -- License     :  FreeBSD
    --
    -- Maintainer  :  Mark Karpov <markkarpov92@gmail.com>
    -- Stability   :  experimental
    -- Portability :  non-portable
    --
    -- High-level parsers to help you write your lexer. The module doesn't
    -- impose how you should write your parser, but certain approaches may be
    -- more elegant than others.
    --
    -- Parsing of white space is an important part of any parser. We propose a
    -- convention where __every lexeme parser assumes no spaces before the__
    -- __lexeme and consumes all spaces after the lexeme__; this is what the
    -- 'lexeme' combinator does, and so it's enough to wrap every lexeme parser
    -- with 'lexeme' to achieve this. Note that you'll need to call 'space'
    -- manually to consume any white space before the first lexeme (i.e. at the
    -- beginning of the file).
    --
    -- This module is intended to be imported qualified:
    --
    -- > import qualified Text.Megaparsec.Char.Lexer as L
    --
    -- To do lexing of byte streams, see "Text.Megaparsec.Byte.Lexer".

    {-# LANGUAGE FlexibleContexts    #-}
    {-# LANGUAGE MultiWayIf          #-}
    {-# LANGUAGE ScopedTypeVariables #-}
    {-# LANGUAGE TypeFamilies        #-}

    module Text.Megaparsec.Char.Lexer
      ( -- * White space
        space
      , lexeme
      , symbol
      , symbol'
      , skipLineComment
      , skipBlockComment
      , skipBlockCommentNested
        -- * Indentation
      , indentLevel
      , incorrectIndent
      , indentGuard
      , nonIndented
      , IndentOpt (..)
      , indentBlock
      , lineFold
        -- * Character and string literals
      , charLiteral
        -- * Numbers
      , decimal
      , binary
      , octal
      , hexadecimal
      , scientific
      , float
      , signed )
    where

    import Control.Applicative
    import Control.Monad (void)
    import Data.List (foldl')
    import Data.List.NonEmpty (NonEmpty (..))
    import Data.Maybe (listToMaybe, fromMaybe, isJust)
    import Data.Proxy
    import Data.Scientific (Scientific)
    import Text.Megaparsec
    import Text.Megaparsec.Lexer
    import qualified Data.Char            as Char
    import qualified Data.Scientific      as Sci
    import qualified Data.Set             as E
    import qualified Text.Megaparsec.Char as C

    ----------------------------------------------------------------------------
    -- White space

    -- | Given comment prefix this function returns a parser that skips line
    -- comments. Note that it stops just before the newline character but
    -- doesn't consume the newline. Newline is either supposed to be consumed by
    -- 'space' parser or picked up manually.

    skipLineComment :: (MonadParsec e s m, Token s ~ Char)
      => Tokens s          -- ^ Line comment prefix
      -> m ()
    skipLineComment :: Tokens s -> m ()
    skipLineComment prefix :: Tokens s
    prefix =
      Tokens s -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Tokens s -> m (Tokens s)
    C.string Tokens s
    prefix m (Tokens s) -> m () -> m ()
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> m (Tokens s) -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void (Maybe String -> (Token s -> Bool) -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Maybe String -> (Token s -> Bool) -> m (Tokens s)
    takeWhileP (String -> Maybe String
    forall a. a -> Maybe a
    Just "character") (Char -> Char -> Bool
    forall a. Eq a => a -> a -> Bool
    /= '\n'))
    {-# INLINEABLE skipLineComment #-}

    -- | @'skipBlockComment' start end@ skips non-nested block comment starting
    -- with @start@ and ending with @end@.

    skipBlockComment :: (MonadParsec e s m, Token s ~ Char)
      => Tokens s          -- ^ Start of block comment
      -> Tokens s          -- ^ End of block comment
      -> m ()
    skipBlockComment :: Tokens s -> Tokens s -> m ()
    skipBlockComment start :: Tokens s
    start end :: Tokens s
    end = m (Tokens s)
    p m (Tokens s) -> m () -> m ()
    forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
    >> m String -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void (m Char -> m (Tokens s) -> m String
    forall (m :: * -> *) a end. MonadPlus m => m a -> m end -> m [a]
    manyTill m Char
    forall e s (m :: * -> *). MonadParsec e s m => m (Token s)
    anySingle m (Tokens s)
    n)
      where
        p :: m (Tokens s)
    p = Tokens s -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Tokens s -> m (Tokens s)
    C.string Tokens s
    start
        n :: m (Tokens s)
    n = Tokens s -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Tokens s -> m (Tokens s)
    C.string Tokens s
    end
    {-# INLINEABLE skipBlockComment #-}

    -- | @'skipBlockCommentNested' start end@ skips possibly nested block
    -- comment starting with @start@ and ending with @end@.
    --
    -- @since 5.0.0

    skipBlockCommentNested :: (MonadParsec e s m, Token s ~ Char)
      => Tokens s          -- ^ Start of block comment
      -> Tokens s          -- ^ End of block comment
      -> m ()
    skipBlockCommentNested :: Tokens s -> Tokens s -> m ()
    skipBlockCommentNested start :: Tokens s
    start end :: Tokens s
    end = m (Tokens s)
    p m (Tokens s) -> m () -> m ()
    forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
    >> m [()] -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void (m () -> m (Tokens s) -> m [()]
    forall (m :: * -> *) a end. MonadPlus m => m a -> m end -> m [a]
    manyTill m ()
    e m (Tokens s)
    n)
      where
        e :: m ()
    e = Tokens s -> Tokens s -> m ()
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Tokens s -> Tokens s -> m ()
    skipBlockCommentNested Tokens s
    start Tokens s
    end m () -> m () -> m ()
    forall (f :: * -> *) a. Alternative f => f a -> f a -> f a
    <|> m Char -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void m Char
    forall e s (m :: * -> *). MonadParsec e s m => m (Token s)
    anySingle
        p :: m (Tokens s)
    p = Tokens s -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Tokens s -> m (Tokens s)
    C.string Tokens s
    start
        n :: m (Tokens s)
    n = Tokens s -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Tokens s -> m (Tokens s)
    C.string Tokens s
    end
    {-# INLINEABLE skipBlockCommentNested #-}

    ----------------------------------------------------------------------------
    -- Indentation

    -- | Return the current indentation level.
    --
    -- The function is a simple shortcut defined as:
    --
    -- > indentLevel = sourceColumn <$> getPosition
    --
    -- @since 4.3.0

    indentLevel :: MonadParsec e s m => m Pos
    indentLevel :: m Pos
    indentLevel = SourcePos -> Pos
    sourceColumn (SourcePos -> Pos) -> m SourcePos -> m Pos
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> m SourcePos
    forall e s (m :: * -> *). MonadParsec e s m => m SourcePos
    getSourcePos
    {-# INLINE indentLevel #-}

    -- | Fail reporting incorrect indentation error. The error has attached
    -- information:
    --
    --     * Desired ordering between reference level and actual level
    --     * Reference indentation level
    --     * Actual indentation level
    --
    -- @since 5.0.0

    incorrectIndent :: MonadParsec e s m
      => Ordering  -- ^ Desired ordering between reference level and actual level
      -> Pos               -- ^ Reference indentation level
      -> Pos               -- ^ Actual indentation level
      -> m a
    incorrectIndent :: Ordering -> Pos -> Pos -> m a
    incorrectIndent ord :: Ordering
    ord ref :: Pos
    ref actual :: Pos
    actual = Set (ErrorFancy e) -> m a
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    Set (ErrorFancy e) -> m a
    fancyFailure (Set (ErrorFancy e) -> m a)
    -> (ErrorFancy e -> Set (ErrorFancy e)) -> ErrorFancy e -> m a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . ErrorFancy e -> Set (ErrorFancy e)
    forall a. a -> Set a
    E.singleton (ErrorFancy e -> m a) -> ErrorFancy e -> m a
    forall a b. (a -> b) -> a -> b
    $
      Ordering -> Pos -> Pos -> ErrorFancy e
    forall e. Ordering -> Pos -> Pos -> ErrorFancy e
    ErrorIndentation Ordering
    ord Pos
    ref Pos
    actual
    {-# INLINEABLE incorrectIndent #-}

    -- | @'indentGuard' spaceConsumer ord ref@ first consumes all white space
    -- (indentation) with @spaceConsumer@ parser, then it checks the column
    -- position. Ordering between current indentation level and the reference
    -- indentation level @ref@ should be @ord@, otherwise the parser fails. On
    -- success the current column position is returned.
    --
    -- When you want to parse a block of indentation, first run this parser with
    -- arguments like @'indentGuard' spaceConsumer 'GT' 'pos1'@—this will make
    -- sure you have some indentation. Use returned value to check indentation
    -- on every subsequent line according to syntax of your language.

    indentGuard :: MonadParsec e s m
      => m ()              -- ^ How to consume indentation (white space)
      -> Ordering -- ^ Desired ordering between reference level and actual level
      -> Pos               -- ^ Reference indentation level
      -> m Pos             -- ^ Current column (indentation level)
    indentGuard :: m () -> Ordering -> Pos -> m Pos
    indentGuard sc :: m ()
    sc ord :: Ordering
    ord ref :: Pos
    ref = do
      m ()
    sc
      Pos
    actual <- m Pos
    forall e s (m :: * -> *). MonadParsec e s m => m Pos
    indentLevel
      if Pos -> Pos -> Ordering
    forall a. Ord a => a -> a -> Ordering
    compare Pos
    actual Pos
    ref Ordering -> Ordering -> Bool
    forall a. Eq a => a -> a -> Bool
    == Ordering
    ord
        then Pos -> m Pos
    forall (m :: * -> *) a. Monad m => a -> m a
    return Pos
    actual
        else Ordering -> Pos -> Pos -> m Pos
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    Ordering -> Pos -> Pos -> m a
    incorrectIndent Ordering
    ord Pos
    ref Pos
    actual
    {-# INLINEABLE indentGuard #-}

    -- | Parse a non-indented construction. This ensures that there is no
    -- indentation before actual data. Useful, for example, as a wrapper for
    -- top-level function definitions.
    --
    -- @since 4.3.0

    nonIndented :: MonadParsec e s m
      => m ()              -- ^ How to consume indentation (white space)
      -> m a               -- ^ How to parse actual data
      -> m a
    nonIndented :: m () -> m a -> m a
    nonIndented sc :: m ()
    sc p :: m a
    p = m () -> Ordering -> Pos -> m Pos
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    m () -> Ordering -> Pos -> m Pos
    indentGuard m ()
    sc Ordering
    EQ Pos
    pos1 m Pos -> m a -> m a
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> m a
    p
    {-# INLINEABLE nonIndented #-}

    -- | Behaviors for parsing of indented tokens. This is used in
    -- 'indentBlock', which see.
    --
    -- @since 4.3.0

    data IndentOpt m a b
      = IndentNone a
        -- ^ Parse no indented tokens, just return the value
      | IndentMany (Maybe Pos) ([b] -> m a) (m b)
        -- ^ Parse many indented tokens (possibly zero), use given indentation
        -- level (if 'Nothing', use level of the first indented token); the
        -- second argument tells how to get the final result, and the third
        -- argument describes how to parse an indented token
      | IndentSome (Maybe Pos) ([b] -> m a) (m b)
        -- ^ Just like 'IndentMany', but requires at least one indented token to
        -- be present

    -- | Parse a “reference” token and a number of other tokens that have
    -- greater (but the same) level of indentation than that of “reference”
    -- token. Reference token can influence parsing, see 'IndentOpt' for more
    -- information.
    --
    -- Tokens /must not/ consume newlines after them. On the other hand, the
    -- first argument of this function /must/ consume newlines among other white
    -- space characters.
    --
    -- @since 4.3.0

    indentBlock :: (MonadParsec e s m, Token s ~ Char)
      => m ()              -- ^ How to consume indentation (white space)
      -> m (IndentOpt m a b) -- ^ How to parse “reference” token
      -> m a
    indentBlock :: m () -> m (IndentOpt m a b) -> m a
    indentBlock sc :: m ()
    sc r :: m (IndentOpt m a b)
    r = do
      m ()
    sc
      Pos
    ref <- m Pos
    forall e s (m :: * -> *). MonadParsec e s m => m Pos
    indentLevel
      IndentOpt m a b
    a   <- m (IndentOpt m a b)
    r
      case IndentOpt m a b
    a of
        IndentNone x :: a
    x -> a
    x a -> m () -> m a
    forall (f :: * -> *) a b. Functor f => a -> f b -> f a
    <$ m ()
    sc
        IndentMany indent :: Maybe Pos
    indent f :: [b] -> m a
    f p :: m b
    p -> do
          Maybe Pos
    mlvl <- (m Pos -> m (Maybe Pos)
    forall (f :: * -> *) a. Alternative f => f a -> f (Maybe a)
    optional (m Pos -> m (Maybe Pos))
    -> (m Pos -> m Pos) -> m Pos -> m (Maybe Pos)
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . m Pos -> m Pos
    forall e s (m :: * -> *) a. MonadParsec e s m => m a -> m a
    try) (m (Tokens s)
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    m (Tokens s)
    C.eol m (Tokens s) -> m Pos -> m Pos
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> m () -> Ordering -> Pos -> m Pos
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    m () -> Ordering -> Pos -> m Pos
    indentGuard m ()
    sc Ordering
    GT Pos
    ref)
          Bool
    done <- Maybe () -> Bool
    forall a. Maybe a -> Bool
    isJust (Maybe () -> Bool) -> m (Maybe ()) -> m Bool
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> m () -> m (Maybe ())
    forall (f :: * -> *) a. Alternative f => f a -> f (Maybe a)
    optional m ()
    forall e s (m :: * -> *). MonadParsec e s m => m ()
    eof
          case (Maybe Pos
    mlvl, Bool
    done) of
            (Just lvl :: Pos
    lvl, False) ->
              Pos -> Pos -> m () -> m b -> m [b]
    forall e s (m :: * -> *) b.
    MonadParsec e s m =>
    Pos -> Pos -> m () -> m b -> m [b]
    indentedItems Pos
    ref (Pos -> Maybe Pos -> Pos
    forall a. a -> Maybe a -> a
    fromMaybe Pos
    lvl Maybe Pos
    indent) m ()
    sc m b
    p m [b] -> ([b] -> m a) -> m a
    forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
    >>= [b] -> m a
    f
            _ -> m ()
    sc m () -> m a -> m a
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> [b] -> m a
    f []
        IndentSome indent :: Maybe Pos
    indent f :: [b] -> m a
    f p :: m b
    p -> do
          Pos
    pos <- m (Tokens s)
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    m (Tokens s)
    C.eol m (Tokens s) -> m Pos -> m Pos
    forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
    *> m () -> Ordering -> Pos -> m Pos
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    m () -> Ordering -> Pos -> m Pos
    indentGuard m ()
    sc Ordering
    GT Pos
    ref
          let lvl :: Pos
    lvl = Pos -> Maybe Pos -> Pos
    forall a. a -> Maybe a -> a
    fromMaybe Pos
    pos Maybe Pos
    indent
          b
    x <- if | Pos
    pos Pos -> Pos -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Pos
    ref -> Ordering -> Pos -> Pos -> m b
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    Ordering -> Pos -> Pos -> m a
    incorrectIndent Ordering
    GT Pos
    ref Pos
    pos
                  | Pos
    pos Pos -> Pos -> Bool
    forall a. Eq a => a -> a -> Bool
    == Pos
    lvl -> m b
    p
                  | Bool
    otherwise  -> Ordering -> Pos -> Pos -> m b
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    Ordering -> Pos -> Pos -> m a
    incorrectIndent Ordering
    EQ Pos
    lvl Pos
    pos
          [b]
    xs  <- Pos -> Pos -> m () -> m b -> m [b]
    forall e s (m :: * -> *) b.
    MonadParsec e s m =>
    Pos -> Pos -> m () -> m b -> m [b]
    indentedItems Pos
    ref Pos
    lvl m ()
    sc m b
    p
          [b] -> m a
    f (b
    xb -> [b] -> [b]
    forall a. a -> [a] -> [a]
    :[b]
    xs)
    {-# INLINEABLE indentBlock #-}

    -- | Grab indented items. This is a helper for 'indentBlock', it's not a
    -- part of the public API.

    indentedItems :: MonadParsec e s m
      => Pos               -- ^ Reference indentation level
      -> Pos               -- ^ Level of the first indented item ('lookAhead'ed)
      -> m ()              -- ^ How to consume indentation (white space)
      -> m b               -- ^ How to parse indented tokens
      -> m [b]
    indentedItems :: Pos -> Pos -> m () -> m b -> m [b]
    indentedItems ref :: Pos
    ref lvl :: Pos
    lvl sc :: m ()
    sc p :: m b
    p = m [b]
    go
      where
        go :: m [b]
    go = do
          m ()
    sc
          Pos
    pos  <- m Pos
    forall e s (m :: * -> *). MonadParsec e s m => m Pos
    indentLevel
          Bool
    done <- Maybe () -> Bool
    forall a. Maybe a -> Bool
    isJust (Maybe () -> Bool) -> m (Maybe ()) -> m Bool
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> m () -> m (Maybe ())
    forall (f :: * -> *) a. Alternative f => f a -> f (Maybe a)
    optional m ()
    forall e s (m :: * -> *). MonadParsec e s m => m ()
    eof
          if Bool
    done
            then [b] -> m [b]
    forall (m :: * -> *) a. Monad m => a -> m a
    return []
            else if | Pos
    pos Pos -> Pos -> Bool
    forall a. Ord a => a -> a -> Bool
    <= Pos
    ref -> [b] -> m [b]
    forall (m :: * -> *) a. Monad m => a -> m a
    return []
                    | Pos
    pos Pos -> Pos -> Bool
    forall a. Eq a => a -> a -> Bool
    == Pos
    lvl -> (:) (b -> [b] -> [b]) -> m b -> m ([b] -> [b])
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> m b
    p m ([b] -> [b]) -> m [b] -> m [b]
    forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
    <*> m [b]
    go
                    | Bool
    otherwise  -> Ordering -> Pos -> Pos -> m [b]
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    Ordering -> Pos -> Pos -> m a
    incorrectIndent Ordering
    EQ Pos
    lvl Pos
    pos

    -- | Create a parser that supports line-folding. The first argument is used
    -- to consume white space between components of line fold, thus it /must/
    -- consume newlines in order to work properly. The second argument is a
    -- callback that receives a custom space-consuming parser as an argument.
    -- This parser should be used after separate components of line fold that
    -- can be put on different lines.
    --
    -- An example should clarify the usage pattern:
    --
    -- > sc = L.space (void spaceChar) empty empty
    -- >
    -- > myFold = L.lineFold sc $ \sc' -> do
    -- >   L.symbol sc' "foo"
    -- >   L.symbol sc' "bar"
    -- >   L.symbol sc  "baz" -- for the last symbol we use normal space consumer
    --
    -- @since 5.0.0

    lineFold :: MonadParsec e s m
      => m ()              -- ^ How to consume indentation (white space)
      -> (m () -> m a)     -- ^ Callback that uses provided space-consumer
      -> m a
    lineFold :: m () -> (m () -> m a) -> m a
    lineFold sc :: m ()
    sc action :: m () -> m a
    action =
      m ()
    sc m () -> m Pos -> m Pos
    forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
    >> m Pos
    forall e s (m :: * -> *). MonadParsec e s m => m Pos
    indentLevel m Pos -> (Pos -> m a) -> m a
    forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
    >>= m () -> m a
    action (m () -> m a) -> (Pos -> m ()) -> Pos -> m a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . m Pos -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void (m Pos -> m ()) -> (Pos -> m Pos) -> Pos -> m ()
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . m () -> Ordering -> Pos -> m Pos
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    m () -> Ordering -> Pos -> m Pos
    indentGuard m ()
    sc Ordering
    GT
    {-# INLINEABLE lineFold #-}

    ----------------------------------------------------------------------------
    -- Character and string literals

    -- | The lexeme parser parses a single literal character without quotes. The
    -- purpose of this parser is to help with parsing of conventional escape
    -- sequences. It's your responsibility to take care of character literal
    -- syntax in your language (by surrounding it with single quotes or
    -- similar).
    --
    -- The literal character is parsed according to the grammar rules defined in
    -- the Haskell report.
    --
    -- Note that you can use this parser as a building block to parse various
    -- string literals:
    --
    -- > stringLiteral = char '"' >> manyTill L.charLiteral (char '"')
    --
    -- __Performance note__: the parser is not particularly efficient at the
    -- moment.

    charLiteral :: (MonadParsec e s m, Token s ~ Char) => m Char
    charLiteral :: m Char
    charLiteral = String -> m Char -> m Char
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    String -> m a -> m a
    label "literal character" (m Char -> m Char) -> m Char -> m Char
    forall a b. (a -> b) -> a -> b
    $ do
      -- The @~@ is needed to avoid requiring a MonadFail constraint,
      -- and we do know that r will be non-empty if count' succeeds.
      String
    r <- m String -> m String
    forall e s (m :: * -> *) a. MonadParsec e s m => m a -> m a
    lookAhead (Int -> Int -> m Char -> m String
    forall (m :: * -> *) a. MonadPlus m => Int -> Int -> m a -> m [a]
    count' 1 10 m Char
    forall e s (m :: * -> *). MonadParsec e s m => m (Token s)
    anySingle)
      case [(Char, String)] -> Maybe (Char, String)
    forall a. [a] -> Maybe a
    listToMaybe (ReadS Char
    Char.readLitChar String
    r) of
        Just (c :: Char
    c, r' :: String
    r') -> Char
    c Char -> m () -> m Char
    forall (f :: * -> *) a b. Functor f => a -> f b -> f a
    <$ Int -> m Char -> m ()
    forall (m :: * -> *) a. Monad m => Int -> m a -> m ()
    skipCount (String -> Int
    forall (t :: * -> *) a. Foldable t => t a -> Int
    length String
    r Int -> Int -> Int
    forall a. Num a => a -> a -> a
    - String -> Int
    forall (t :: * -> *) a. Foldable t => t a -> Int
    length String
    r') m Char
    forall e s (m :: * -> *). MonadParsec e s m => m (Token s)
    anySingle
        Nothing      -> ErrorItem (Token s) -> m Char
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    ErrorItem (Token s) -> m a
    unexpected (NonEmpty Char -> ErrorItem Char
    forall t. NonEmpty t -> ErrorItem t
    Tokens (String -> Char
    forall a. [a] -> a
    head String
    rChar -> String -> NonEmpty Char
    forall a. a -> [a] -> NonEmpty a
    :|[]))
    {-# INLINEABLE charLiteral #-}

    ----------------------------------------------------------------------------
    -- Numbers

    -- | Parse an integer in decimal representation according to the format of
    -- integer literals described in the Haskell report.
    --
    -- If you need to parse signed integers, see the 'signed' combinator.
    --
    -- __Note__: before version 6.0.0 the function returned 'Integer', i.e. it
    -- wasn't polymorphic in its return type.

    decimal :: (MonadParsec e s m, Token s ~ Char, Num a) => m a
    decimal :: m a
    decimal = m a
    forall e s (m :: * -> *) a.
    (MonadParsec e s m, Token s ~ Char, Num a) =>
    m a
    decimal_ m a -> String -> m a
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    m a -> String -> m a
    <?> "integer"
    {-# INLINEABLE decimal #-}

    -- | A non-public helper to parse decimal integers.

    decimal_
      :: forall e s m a. (MonadParsec e s m, Token s ~ Char, Num a)
      => m a
    decimal_ :: m a
    decimal_ = Tokens s -> a
    mkNum (Tokens s -> a) -> m (Tokens s) -> m a
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> Maybe String -> (Token s -> Bool) -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Maybe String -> (Token s -> Bool) -> m (Tokens s)
    takeWhile1P (String -> Maybe String
    forall a. a -> Maybe a
    Just "digit") Char -> Bool
    Token s -> Bool
    Char.isDigit
      where
        mkNum :: Tokens s -> a
    mkNum    = (a -> Char -> a) -> a -> String -> a
    forall (t :: * -> *) b a.
    Foldable t =>
    (b -> a -> b) -> b -> t a -> b
    foldl' a -> Char -> a
    forall a. Num a => a -> Char -> a
    step 0 (String -> a) -> (Tokens s -> String) -> Tokens s -> a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Proxy s -> Tokens s -> [Token s]
    forall s. Stream s => Proxy s -> Tokens s -> [Token s]
    chunkToTokens (Proxy s
    forall k (t :: k). Proxy t
    Proxy :: Proxy s)
        step :: a -> Char -> a
    step a :: a
    a c :: Char
    c = a
    a a -> a -> a
    forall a. Num a => a -> a -> a
    * 10 a -> a -> a
    forall a. Num a => a -> a -> a
    + Int -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (Char -> Int
    Char.digitToInt Char
    c)
    {-# INLINE decimal_ #-}

    -- | Parse an integer in binary representation. Binary number is expected to
    -- be a non-empty sequence of zeroes “0” and ones “1”.
    --
    -- You could of course parse some prefix before the actual number:
    --
    -- > binary = char '0' >> char' 'b' >> L.binary
    --
    -- @since 7.0.0

    binary
      :: forall e s m a. (MonadParsec e s m, Token s ~ Char, Num a)
      => m a
    binary :: m a
    binary = Tokens s -> a
    mkNum
      (Tokens s -> a) -> m (Tokens s) -> m a
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> Maybe String -> (Token s -> Bool) -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Maybe String -> (Token s -> Bool) -> m (Tokens s)
    takeWhile1P Maybe String
    forall a. Maybe a
    Nothing Char -> Bool
    Token s -> Bool
    isBinDigit
      m a -> String -> m a
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    m a -> String -> m a
    <?> "binary integer"
      where
        mkNum :: Tokens s -> a
    mkNum        = (a -> Char -> a) -> a -> String -> a
    forall (t :: * -> *) b a.
    Foldable t =>
    (b -> a -> b) -> b -> t a -> b
    foldl' a -> Char -> a
    forall a. Num a => a -> Char -> a
    step 0 (String -> a) -> (Tokens s -> String) -> Tokens s -> a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Proxy s -> Tokens s -> [Token s]
    forall s. Stream s => Proxy s -> Tokens s -> [Token s]
    chunkToTokens (Proxy s
    forall k (t :: k). Proxy t
    Proxy :: Proxy s)
        step :: a -> Char -> a
    step a :: a
    a c :: Char
    c     = a
    a a -> a -> a
    forall a. Num a => a -> a -> a
    * 2 a -> a -> a
    forall a. Num a => a -> a -> a
    + Int -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (Char -> Int
    Char.digitToInt Char
    c)
        isBinDigit :: Char -> Bool
    isBinDigit x :: Char
    x = Char
    x Char -> Char -> Bool
    forall a. Eq a => a -> a -> Bool
    == '0' Bool -> Bool -> Bool
    || Char
    x Char -> Char -> Bool
    forall a. Eq a => a -> a -> Bool
    == '1'
    {-# INLINEABLE binary #-}

    -- | Parse an integer in octal representation. Representation of octal
    -- number is expected to be according to the Haskell report except for the
    -- fact that this parser doesn't parse “0o” or “0O” prefix. It is a
    -- responsibility of the programmer to parse correct prefix before parsing
    -- the number itself.
    --
    -- For example you can make it conform to the Haskell report like this:
    --
    -- > octal = char '0' >> char' 'o' >> L.octal
    --
    -- __Note__: before version 6.0.0 the function returned 'Integer', i.e. it
    -- wasn't polymorphic in its return type.

    octal
      :: forall e s m a. (MonadParsec e s m, Token s ~ Char, Num a)
      => m a
    octal :: m a
    octal = Tokens s -> a
    mkNum
      (Tokens s -> a) -> m (Tokens s) -> m a
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> Maybe String -> (Token s -> Bool) -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Maybe String -> (Token s -> Bool) -> m (Tokens s)
    takeWhile1P Maybe String
    forall a. Maybe a
    Nothing Char -> Bool
    Token s -> Bool
    Char.isOctDigit
      m a -> String -> m a
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    m a -> String -> m a
    <?> "octal integer"
      where
        mkNum :: Tokens s -> a
    mkNum    = (a -> Char -> a) -> a -> String -> a
    forall (t :: * -> *) b a.
    Foldable t =>
    (b -> a -> b) -> b -> t a -> b
    foldl' a -> Char -> a
    forall a. Num a => a -> Char -> a
    step 0 (String -> a) -> (Tokens s -> String) -> Tokens s -> a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Proxy s -> Tokens s -> [Token s]
    forall s. Stream s => Proxy s -> Tokens s -> [Token s]
    chunkToTokens (Proxy s
    forall k (t :: k). Proxy t
    Proxy :: Proxy s)
        step :: a -> Char -> a
    step a :: a
    a c :: Char
    c = a
    a a -> a -> a
    forall a. Num a => a -> a -> a
    * 8 a -> a -> a
    forall a. Num a => a -> a -> a
    + Int -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (Char -> Int
    Char.digitToInt Char
    c)
    {-# INLINEABLE octal #-}

    -- | Parse an integer in hexadecimal representation. Representation of
    -- hexadecimal number is expected to be according to the Haskell report
    -- except for the fact that this parser doesn't parse “0x” or “0X” prefix.
    -- It is a responsibility of the programmer to parse correct prefix before
    -- parsing the number itself.
    --
    -- For example you can make it conform to the Haskell report like this:
    --
    -- > hexadecimal = char '0' >> char' 'x' >> L.hexadecimal
    --
    -- __Note__: before version 6.0.0 the function returned 'Integer', i.e. it
    -- wasn't polymorphic in its return type.

    hexadecimal
      :: forall e s m a. (MonadParsec e s m, Token s ~ Char, Num a)
      => m a
    hexadecimal :: m a
    hexadecimal = Tokens s -> a
    mkNum
      (Tokens s -> a) -> m (Tokens s) -> m a
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> Maybe String -> (Token s -> Bool) -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Maybe String -> (Token s -> Bool) -> m (Tokens s)
    takeWhile1P Maybe String
    forall a. Maybe a
    Nothing Char -> Bool
    Token s -> Bool
    Char.isHexDigit
      m a -> String -> m a
    forall e s (m :: * -> *) a.
    MonadParsec e s m =>
    m a -> String -> m a
    <?> "hexadecimal integer"
      where
        mkNum :: Tokens s -> a
    mkNum    = (a -> Char -> a) -> a -> String -> a
    forall (t :: * -> *) b a.
    Foldable t =>
    (b -> a -> b) -> b -> t a -> b
    foldl' a -> Char -> a
    forall a. Num a => a -> Char -> a
    step 0 (String -> a) -> (Tokens s -> String) -> Tokens s -> a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Proxy s -> Tokens s -> [Token s]
    forall s. Stream s => Proxy s -> Tokens s -> [Token s]
    chunkToTokens (Proxy s
    forall k (t :: k). Proxy t
    Proxy :: Proxy s)
        step :: a -> Char -> a
    step a :: a
    a c :: Char
    c = a
    a a -> a -> a
    forall a. Num a => a -> a -> a
    * 16 a -> a -> a
    forall a. Num a => a -> a -> a
    + Int -> a
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (Char -> Int
    Char.digitToInt Char
    c)
    {-# INLINEABLE hexadecimal #-}

    -- | Parse a floating point value as a 'Scientific' number. 'Scientific' is
    -- great for parsing of arbitrary precision numbers coming from an untrusted
    -- source. See documentation in "Data.Scientific" for more information.
    --
    -- The parser can be used to parse integers or floating point values. Use
    -- functions like 'Data.Scientific.floatingOrInteger' from "Data.Scientific"
    -- to test and extract integer or real values.
    --
    -- This function does not parse sign, if you need to parse signed numbers,
    -- see 'signed'.
    --
    -- @since 5.0.0

    scientific
      :: forall e s m. (MonadParsec e s m, Token s ~ Char)
      => m Scientific
    scientific :: m Scientific
    scientific = do
      Integer
    c'      <- m Integer
    forall e s (m :: * -> *) a.
    (MonadParsec e s m, Token s ~ Char, Num a) =>
    m a
    decimal_
      SP c :: Integer
    c e' :: Int
    e' <- SP -> m SP -> m SP
    forall (m :: * -> *) a. Alternative m => a -> m a -> m a
    option (Integer -> Int -> SP
    SP Integer
    c' 0) (m SP -> m SP
    forall e s (m :: * -> *) a. MonadParsec e s m => m a -> m a
    try (m SP -> m SP) -> m SP -> m SP
    forall a b. (a -> b) -> a -> b
    $ Proxy s -> Integer -> m SP
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Proxy s -> Integer -> m SP
    dotDecimal_ (Proxy s
    forall k (t :: k). Proxy t
    Proxy :: Proxy s) Integer
    c')
      Int
    e       <- Int -> m Int -> m Int
    forall (m :: * -> *) a. Alternative m => a -> m a -> m a
    option Int
    e' (m Int -> m Int
    forall e s (m :: * -> *) a. MonadParsec e s m => m a -> m a
    try (m Int -> m Int) -> m Int -> m Int
    forall a b. (a -> b) -> a -> b
    $ Int -> m Int
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Int -> m Int
    exponent_ Int
    e')
      Scientific -> m Scientific
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Integer -> Int -> Scientific
    Sci.scientific Integer
    c Int
    e)
    {-# INLINEABLE scientific #-}

    data SP = SP !Integer {-# UNPACK #-} !Int

    -- | Parse a floating point number according to the syntax for floating
    -- point literals described in the Haskell report.
    --
    -- This function does not parse sign, if you need to parse signed numbers,
    -- see 'signed'.
    --
    -- __Note__: before version 6.0.0 the function returned 'Double', i.e. it
    -- wasn't polymorphic in its return type.
    --
    -- __Note__: in versions 6.0.0–6.1.1 this function accepted plain integers.

    float :: (MonadParsec e s m, Token s ~ Char, RealFloat a) => m a
    float :: m a
    float = do
      Integer
    c' <- m Integer
    forall e s (m :: * -> *) a.
    (MonadParsec e s m, Token s ~ Char, Num a) =>
    m a
    decimal_
      Scientific -> a
    forall a. RealFloat a => Scientific -> a
    Sci.toRealFloat (Scientific -> a) -> m Scientific -> m a
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$>
        ((do SP c :: Integer
    c e' :: Int
    e' <- Proxy s -> Integer -> m SP
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Proxy s -> Integer -> m SP
    dotDecimal_ (forall s. Proxy s
    forall k (t :: k). Proxy t
    Proxy :: Proxy s) Integer
    c'
             Int
    e       <- Int -> m Int -> m Int
    forall (m :: * -> *) a. Alternative m => a -> m a -> m a
    option Int
    e' (m Int -> m Int
    forall e s (m :: * -> *) a. MonadParsec e s m => m a -> m a
    try (m Int -> m Int) -> m Int -> m Int
    forall a b. (a -> b) -> a -> b
    $ Int -> m Int
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Int -> m Int
    exponent_ Int
    e')
             Scientific -> m Scientific
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Integer -> Int -> Scientific
    Sci.scientific Integer
    c Int
    e))
         m Scientific -> m Scientific -> m Scientific
    forall (f :: * -> *) a. Alternative f => f a -> f a -> f a
    <|> (Integer -> Int -> Scientific
    Sci.scientific Integer
    c' (Int -> Scientific) -> m Int -> m Scientific
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> Int -> m Int
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Int -> m Int
    exponent_ 0))
    {-# INLINEABLE float #-}

    dotDecimal_ :: (MonadParsec e s m, Token s ~ Char)
      => Proxy s
      -> Integer
      -> m SP
    dotDecimal_ :: Proxy s -> Integer -> m SP
    dotDecimal_ pxy :: Proxy s
    pxy c' :: Integer
    c' = do
      m Char -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void (Token s -> m (Token s)
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Token s -> m (Token s)
    C.char Token s
    '.')
      let mkNum :: Tokens s -> SP
    mkNum    = (SP -> Char -> SP) -> SP -> String -> SP
    forall (t :: * -> *) b a.
    Foldable t =>
    (b -> a -> b) -> b -> t a -> b
    foldl' SP -> Char -> SP
    step (Integer -> Int -> SP
    SP Integer
    c' 0) (String -> SP) -> (Tokens s -> String) -> Tokens s -> SP
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Proxy s -> Tokens s -> [Token s]
    forall s. Stream s => Proxy s -> Tokens s -> [Token s]
    chunkToTokens Proxy s
    pxy
          step :: SP -> Char -> SP
    step (SP a :: Integer
    a e' :: Int
    e') c :: Char
    c = Integer -> Int -> SP
    SP
            (Integer
    a Integer -> Integer -> Integer
    forall a. Num a => a -> a -> a
    * 10 Integer -> Integer -> Integer
    forall a. Num a => a -> a -> a
    + Int -> Integer
    forall a b. (Integral a, Num b) => a -> b
    fromIntegral (Char -> Int
    Char.digitToInt Char
    c))
            (Int
    e' Int -> Int -> Int
    forall a. Num a => a -> a -> a
    - 1)
      Tokens s -> SP
    mkNum (Tokens s -> SP) -> m (Tokens s) -> m SP
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> Maybe String -> (Token s -> Bool) -> m (Tokens s)
    forall e s (m :: * -> *).
    MonadParsec e s m =>
    Maybe String -> (Token s -> Bool) -> m (Tokens s)
    takeWhile1P (String -> Maybe String
    forall a. a -> Maybe a
    Just "digit") Char -> Bool
    Token s -> Bool
    Char.isDigit
    {-# INLINE dotDecimal_ #-}

    exponent_ :: (MonadParsec e s m, Token s ~ Char)
      => Int
      -> m Int
    exponent_ :: Int -> m Int
    exponent_ e' :: Int
    e' = do
      m Char -> m ()
    forall (f :: * -> *) a. Functor f => f a -> f ()
    void (Token s -> m (Token s)
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Token s -> m (Token s)
    C.char' Token s
    'e')
      (Int -> Int -> Int
    forall a. Num a => a -> a -> a
    + Int
    e') (Int -> Int) -> m Int -> m Int
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> m () -> m Int -> m Int
    forall e s (m :: * -> *) a.
    (MonadParsec e s m, Token s ~ Char, Num a) =>
    m () -> m a -> m a
    signed (() -> m ()
    forall (m :: * -> *) a. Monad m => a -> m a
    return ()) m Int
    forall e s (m :: * -> *) a.
    (MonadParsec e s m, Token s ~ Char, Num a) =>
    m a
    decimal_
    {-# INLINE exponent_ #-}

    -- | @'signed' space p@ parser parses an optional sign character (“+” or
    -- “-”), then if there is a sign it consumes optional white space (using
    -- @space@ parser), then it runs parser @p@ which should return a number.
    -- Sign of the number is changed according to the previously parsed sign
    -- character.
    --
    -- For example, to parse signed integer you can write:
    --
    -- > lexeme        = L.lexeme spaceConsumer
    -- > integer       = lexeme L.decimal
    -- > signedInteger = L.signed spaceConsumer integer

    signed :: (MonadParsec e s m, Token s ~ Char, Num a)
      => m ()              -- ^ How to consume white space after the sign
      -> m a               -- ^ How to parse the number itself
      -> m a               -- ^ Parser for signed numbers
    signed :: m () -> m a -> m a
    signed spc :: m ()
    spc p :: m a
    p = (a -> a) -> m (a -> a) -> m (a -> a)
    forall (m :: * -> *) a. Alternative m => a -> m a -> m a
    option a -> a
    forall a. a -> a
    id (m () -> m (a -> a) -> m (a -> a)
    forall e s (m :: * -> *) a. MonadParsec e s m => m () -> m a -> m a
    lexeme m ()
    spc m (a -> a)
    sign) m (a -> a) -> m a -> m a
    forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
    <*> m a
    p
      where
        sign :: m (a -> a)
    sign = (a -> a
    forall a. a -> a
    id (a -> a) -> m Char -> m (a -> a)
    forall (f :: * -> *) a b. Functor f => a -> f b -> f a
    <$ Token s -> m (Token s)
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Token s -> m (Token s)
    C.char Token s
    '+') m (a -> a) -> m (a -> a) -> m (a -> a)
    forall (f :: * -> *) a. Alternative f => f a -> f a -> f a
    <|> (a -> a
    forall a. Num a => a -> a
    negate (a -> a) -> m Char -> m (a -> a)
    forall (f :: * -> *) a b. Functor f => a -> f b -> f a
    <$ Token s -> m (Token s)
    forall e s (m :: * -> *).
    (MonadParsec e s m, Token s ~ Char) =>
    Token s -> m (Token s)
    C.char Token s
    '-')
    {-# INLINEABLE signed #-}