{-# OPTIONS_GHC -Wno-orphans  #-}

-- |
-- Module      : Streamly.Internal.Data.Parser
-- Copyright   : (c) 2020 Composewell Technologies
-- License     : BSD-3-Clause
-- Maintainer  : streamly@composewell.com
-- Stability   : pre-release
-- Portability : GHC
--
-- Fast backtracking parsers with stream fusion and native streaming
-- capability.
--
-- 'Applicative' and 'Control.Applicative.Alternative' type class based
-- combinators from the
-- <http://hackage.haskell.org/package/parser-combinators parser-combinators>
-- package can also be used with the 'Parser' type. However, there are two
-- important differences between @parser-combinators@ and the equivalent ones
-- provided in this module in terms of performance:
--
-- 1) @parser-combinators@ use plain Haskell lists to collect the results, in a
-- strict Monad like IO, the results are necessarily buffered before they can
-- be consumed.  This may not perform optimally in streaming applications
-- processing large amounts of data.  Equivalent combinators in this module can
-- consume the results of parsing using a 'Fold', thus providing a scalability
-- and a composable consumer.
--
-- 2) Several combinators in this module can be many times faster because of
-- stream fusion. For example, 'Streamly.Internal.Data.Parser.many' combinator
-- in this module is much faster than the 'Control.Applicative.many' combinator
-- of 'Control.Applicative.Alternative' type class.
--
-- = Errors
--
-- Failing parsers in this module throw the 'D.ParseError' exception.
--
-- = Naming
--
-- As far as possible, try that the names of the combinators in this module are
-- consistent with:
--
-- * <https://hackage.haskell.org/package/base/docs/Text-ParserCombinators-ReadP.html base/Text.ParserCombinators.ReadP>
-- * <http://hackage.haskell.org/package/parser-combinators parser-combinators>
-- * <http://hackage.haskell.org/package/megaparsec megaparsec>
-- * <http://hackage.haskell.org/package/attoparsec attoparsec>
-- * <http://hackage.haskell.org/package/parsec parsec>

module Streamly.Internal.Data.Parser
    (
      K.Parser (..)
    , D.ParseError (..)
    , D.Step (..)

    -- * Downgrade to Fold
    , toFold

    -- First order parsers
    -- * Accumulators
    , fromFold
    , fromPure
    , fromEffect
    , die
    , dieM

    -- * Element parsers
    , peek
    , eof
    , satisfy
    , next
    , maybe
    , either

    -- * Sequence parsers
    --
    -- | Parsers chained in series, if one parser terminates the composition
    -- terminates.

    -- | Grab a sequence of input elements without inspecting them
    , takeBetween
    -- , take   -- takeBetween 0 n
    , takeEQ -- takeBetween n n
    , takeGE -- takeBetween n maxBound

    -- Grab a sequence of input elements by inspecting them
    , takeP
    , lookAhead
    , takeWhileP
    , takeWhile
    -- $takeWhile
    , takeWhile1
    , drainWhile

    , sliceSepByP
    , sliceBeginWith
    , sliceSepWith
    , escapedSliceSepBy
    , escapedFrameBy
    , wordBy
    , groupBy
    , groupByRolling
    , groupByRollingEither
    , eqBy
    -- | Unimplemented
    --
    -- @
    -- , prefixOf -- match any prefix of a given string
    -- , suffixOf -- match any suffix of a given string
    -- , infixOf -- match any substring of a given string
    -- @

    -- Second order parsers (parsers using parsers)
    -- * Binary Combinators

    -- ** Sequential Applicative
    , serialWith
    , split_

    -- ** Parallel Applicatives
    , teeWith
    , teeWithFst
    , teeWithMin
    -- , teeTill -- like manyTill but parallel

    -- ** Sequential Interleaving
    -- Use two folds, run a primary parser, its rejected values go to the
    -- secondary parser.
    , deintercalate

    -- ** Sequential Alternative
    , alt

    -- ** Parallel Alternatives
    , shortest
    , longest
    -- , fastest

    -- * N-ary Combinators
    -- ** Sequential Collection
    , concatSequence
    , concatMap

    -- ** Sequential Repetition
    , count
    , countBetween

    , manyP
    , many
    , some
    , manyTillP
    , manyTill
    , manyThen

    -- ** Special cases
    -- | TODO: traditional implmentations of these may be of limited use. For
    -- example, consider parsing lines separated by @\\r\\n@. The main parser
    -- will have to detect and exclude the sequence @\\r\\n@ anyway so that we
    -- can apply the "sep" parser.
    --
    -- We can instead implement these as special cases of deintercalate.
    --
    -- @
    -- , endBy
    -- , sepBy
    -- , sepEndBy
    -- , beginBy
    -- , sepBeginBy
    -- , sepAroundBy
    -- @

    -- * Distribution
    --
    -- | A simple and stupid impl would be to just convert the stream to an
    -- array and give the array reference to all consumers. The array can be
    -- grown on demand by any consumer and truncated when nonbody needs it.

    -- ** Distribute to collection
    -- ** Distribute to repetition

    -- ** Interleaved collection
    -- |
    --
    -- 1. Round robin
    -- 2. Priority based
    , roundRobin

    -- ** Collection of Alternatives
    -- | Unimplemented
    --
    -- @
    -- , shortestN
    -- , longestN
    -- , fastestN -- first N successful in time
    -- , choiceN  -- first N successful in position
    -- @
    , choice   -- first successful in position

    -- ** Repeated Alternatives
    , retryMaxTotal
    , retryMaxSuccessive
    , retry
    )
where

import Control.Monad.Catch (MonadCatch, MonadThrow)
import Prelude
       hiding (any, all, take, takeWhile, sequence, concatMap, maybe, either)

import Streamly.Internal.Data.Fold.Type (Fold(..))
import Streamly.Internal.Data.Parser.ParserK.Type (Parser)

import qualified Streamly.Internal.Data.Fold.Type as FL
import qualified Streamly.Internal.Data.Parser.ParserD as D
import qualified Streamly.Internal.Data.Parser.ParserK.Type as K

--
-- $setup
-- >>> :m
-- >>> import Prelude hiding (any, all, take, takeWhile, sequence, concatMap, maybe, either)
-- >>> import qualified Streamly.Prelude as Stream
-- >>> import qualified Streamly.Internal.Data.Stream.IsStream as Stream (parse, parseMany)
-- >>> import qualified Streamly.Data.Fold as Fold
-- >>> import qualified Streamly.Internal.Data.Parser as Parser

-------------------------------------------------------------------------------
-- Downgrade a parser to a Fold
-------------------------------------------------------------------------------
--
-- | Make a 'Fold' from a 'Parser'. The fold just throws an exception if the
-- parser fails or tries to backtrack.
--
-- This can be useful in combinators that accept a Fold and we know that a
-- Parser cannot fail or failure exception is acceptable as there is no way to
-- recover.
--
-- /Pre-release/
--
{-# INLINE toFold #-}
toFold :: MonadThrow m => Parser m a b -> Fold m a b
toFold :: forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Fold m a b
toFold Parser m a b
p = forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Fold m a b
D.toFold forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p

-------------------------------------------------------------------------------
-- Upgrade folds to parses
-------------------------------------------------------------------------------
--
-- | Make a 'Parser' from a 'Fold'.
--
-- /Pre-release/
--
{-# INLINE fromFold #-}
fromFold :: MonadCatch m => Fold m a b -> Parser m a b
fromFold :: forall (m :: * -> *) a b.
MonadCatch m =>
Fold m a b -> Parser m a b
fromFold = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b. Monad m => Fold m a b -> Parser m a b
D.fromFold

-------------------------------------------------------------------------------
-- Terminating but not failing folds
-------------------------------------------------------------------------------
--
-- This is the dual of stream "fromPure".
--
-- | A parser that always yields a pure value without consuming any input.
--
-- /Pre-release/
--
{-# INLINE [3] fromPure #-}
fromPure :: MonadCatch m => b -> Parser m a b
fromPure :: forall (m :: * -> *) b a. MonadCatch m => b -> Parser m a b
fromPure = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) b a. Monad m => b -> Parser m a b
D.fromPure
{-# RULES "fromPure fallback to CPS" [2]
    forall a. K.toParserK (D.fromPure a) = K.fromPure a #-}

-- This is the dual of stream "fromEffect".
--
-- | A parser that always yields the result of an effectful action without
-- consuming any input.
--
-- /Pre-release/
--
{-# INLINE fromEffect #-}
fromEffect :: MonadCatch m => m b -> Parser m a b
fromEffect :: forall (m :: * -> *) b a. MonadCatch m => m b -> Parser m a b
fromEffect = forall (m :: * -> *) b a. Monad m => m b -> Parser m a b
K.fromEffect -- K.toParserK . D.fromEffect

-- This is the dual of "nil".
--
-- | A parser that always fails with an error message without consuming
-- any input.
--
-- /Pre-release/
--
{-# INLINE [3] die #-}
die :: MonadCatch m => String -> Parser m a b
die :: forall (m :: * -> *) a b. MonadCatch m => String -> Parser m a b
die = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b. MonadThrow m => String -> Parser m a b
D.die
{-# RULES "die fallback to CPS" [2]
    forall a. K.toParserK (D.die a) = K.die a #-}

-- This is the dual of "nilM".
--
-- | A parser that always fails with an effectful error message and without
-- consuming any input.
--
-- /Pre-release/
--
{-# INLINE dieM #-}
dieM :: MonadCatch m => m String -> Parser m a b
dieM :: forall (m :: * -> *) a b. MonadCatch m => m String -> Parser m a b
dieM = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b. MonadThrow m => m String -> Parser m a b
D.dieM

-------------------------------------------------------------------------------
-- Failing Parsers
-------------------------------------------------------------------------------

-- | Peek the head element of a stream, without consuming it. Fails if it
-- encounters end of input.
--
-- >>> Stream.parse ((,) <$> Parser.peek <*> Parser.satisfy (> 0)) $ Stream.fromList [1]
-- (1,1)
--
-- @
-- peek = lookAhead (satisfy True)
-- @
--
-- /Pre-release/
--
{-# INLINE peek #-}
peek :: MonadCatch m => Parser m a a
peek :: forall (m :: * -> *) a. MonadCatch m => Parser m a a
peek = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall (m :: * -> *) a. MonadThrow m => Parser m a a
D.peek

-- | Succeeds if we are at the end of input, fails otherwise.
--
-- >>> Stream.parse ((,) <$> Parser.satisfy (> 0) <*> Parser.eof) $ Stream.fromList [1]
-- (1,())
--
-- /Pre-release/
--
{-# INLINE eof #-}
eof :: MonadCatch m => Parser m a ()
eof :: forall (m :: * -> *) a. MonadCatch m => Parser m a ()
eof = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall (m :: * -> *) a. Monad m => Parser m a ()
D.eof

-- | Returns the next element if it passes the predicate, fails otherwise.
--
-- >>> Stream.parse (Parser.satisfy (== 1)) $ Stream.fromList [1,0,1]
-- 1
--
-- /Pre-release/
--
{-# INLINE satisfy #-}
satisfy :: MonadCatch m => (a -> Bool) -> Parser m a a
satisfy :: forall (m :: * -> *) a. MonadCatch m => (a -> Bool) -> Parser m a a
satisfy = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a. MonadThrow m => (a -> Bool) -> Parser m a a
D.satisfy

-- | Return the next element of the input. Returns 'Nothing'
-- on end of input. Also known as 'head'.
--
-- /Pre-release/
--
{-# INLINE next #-}
next :: MonadCatch m => Parser m a (Maybe a)
next :: forall (m :: * -> *) a. MonadCatch m => Parser m a (Maybe a)
next = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall (m :: * -> *) a. Monad m => Parser m a (Maybe a)
D.next

-- | Map a 'Maybe' returning function on the next element in the stream. The
-- parser fails if the function returns 'Nothing' otherwise returns the 'Just'
-- value.
--
-- /Pre-release/
--
{-# INLINE maybe #-}
maybe :: MonadCatch m => (a -> Maybe b) -> Parser m a b
maybe :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Maybe b) -> Parser m a b
maybe = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadThrow m =>
(a -> Maybe b) -> Parser m a b
D.maybe

-- | Map an 'Either' returning function on the next element in the stream.  If
-- the function returns 'Left err', the parser fails with the error message
-- @err@ otherwise returns the 'Right' value.
--
-- /Pre-release/
--
{-# INLINE either #-}
either :: MonadCatch m => (a -> Either String b) -> Parser m a b
either :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Either String b) -> Parser m a b
either = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadThrow m =>
(a -> Either String b) -> Parser m a b
D.either

-------------------------------------------------------------------------------
-- Taking elements
-------------------------------------------------------------------------------

-- | @takeBetween m n@ takes a minimum of @m@ and a maximum of @n@ input
-- elements and folds them using the supplied fold.
--
-- Stops after @n@ elements.
-- Fails if the stream ends before @m@ elements could be taken.
--
-- Examples: -
--
-- @
-- >>> :{
--   takeBetween' low high ls = Stream.parse prsr (Stream.fromList ls)
--     where prsr = Parser.takeBetween low high Fold.toList
-- :}
--
-- @
--
-- >>> takeBetween' 2 4 [1, 2, 3, 4, 5]
-- [1,2,3,4]
--
-- >>> takeBetween' 2 4 [1, 2]
-- [1,2]
--
-- >>> takeBetween' 2 4 [1]
-- *** Exception: ParseError "takeBetween: Expecting alteast 2 elements, got 1"
--
-- >>> takeBetween' 0 0 [1, 2]
-- []
--
-- >>> takeBetween' 0 1 []
-- []
--
-- @takeBetween@ is the most general take operation, other take operations can
-- be defined in terms of takeBetween. For example:
--
-- @
-- take = takeBetween 0 n  -- equivalent of take
-- take1 = takeBetween 1 n -- equivalent of takeLE1
-- takeEQ = takeBetween n n
-- takeGE = takeBetween n maxBound
-- @
--
-- /Pre-release/
--
{-# INLINE takeBetween #-}
takeBetween ::  MonadCatch m =>
    Int -> Int -> Fold m a b -> Parser m a b
takeBetween :: forall (m :: * -> *) a b.
MonadCatch m =>
Int -> Int -> Fold m a b -> Parser m a b
takeBetween Int
m Int
n = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadCatch m =>
Int -> Int -> Fold m a b -> Parser m a b
D.takeBetween Int
m Int
n

-- | Stops after taking exactly @n@ input elements.
--
-- * Stops - after consuming @n@ elements.
-- * Fails - if the stream or the collecting fold ends before it can collect
--           exactly @n@ elements.
--
-- >>> Stream.parse (Parser.takeEQ 4 Fold.toList) $ Stream.fromList [1,0,1]
-- *** Exception: ParseError "takeEQ: Expecting exactly 4 elements, input terminated on 3"
--
-- /Pre-release/
--
{-# INLINE takeEQ #-}
takeEQ :: MonadCatch m => Int -> Fold m a b -> Parser m a b
takeEQ :: forall (m :: * -> *) a b.
MonadCatch m =>
Int -> Fold m a b -> Parser m a b
takeEQ Int
n = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadThrow m =>
Int -> Fold m a b -> Parser m a b
D.takeEQ Int
n

-- | Take at least @n@ input elements, but can collect more.
--
-- * Stops - when the collecting fold stops.
-- * Fails - if the stream or the collecting fold ends before producing @n@
--           elements.
--
-- >>> Stream.parse (Parser.takeGE 4 Fold.toList) $ Stream.fromList [1,0,1]
-- *** Exception: ParseError "takeGE: Expecting at least 4 elements, input terminated on 3"
--
-- >>> Stream.parse (Parser.takeGE 4 Fold.toList) $ Stream.fromList [1,0,1,0,1]
-- [1,0,1,0,1]
--
-- /Pre-release/
--
{-# INLINE takeGE #-}
takeGE :: MonadCatch m => Int -> Fold m a b -> Parser m a b
takeGE :: forall (m :: * -> *) a b.
MonadCatch m =>
Int -> Fold m a b -> Parser m a b
takeGE Int
n = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadThrow m =>
Int -> Fold m a b -> Parser m a b
D.takeGE Int
n

-- $takeWhile
-- Note: This is called @takeWhileP@ and @munch@ in some parser libraries.

-- | Like 'takeWhile' but uses a 'Parser' instead of a 'Fold' to collect the
-- input. The combinator stops when the condition fails or if the collecting
-- parser stops.
--
-- This is a generalized version of takeWhile, for example 'takeWhile1' can be
-- implemented in terms of this:
--
-- @
-- takeWhile1 cond p = takeWhile cond (takeBetween 1 maxBound p)
-- @
--
-- Stops: when the condition fails or the collecting parser stops.
-- Fails: when the collecting parser fails.
--
-- /Unimplemented/
--
{-# INLINE takeWhileP #-}
takeWhileP :: -- MonadCatch m =>
    (a -> Bool) -> Parser m a b -> Parser m a b
takeWhileP :: forall a (m :: * -> *) b.
(a -> Bool) -> Parser m a b -> Parser m a b
takeWhileP a -> Bool
_cond = forall a. HasCallStack => a
undefined -- K.toParserK . D.takeWhileP cond

-- | Collect stream elements until an element fails the predicate. The element
-- on which the predicate fails is returned back to the input stream.
--
-- * Stops - when the predicate fails or the collecting fold stops.
-- * Fails - never.
--
-- >>> Stream.parse (Parser.takeWhile (== 0) Fold.toList) $ Stream.fromList [0,0,1,0,1]
-- [0,0]
--
-- We can implement a @breakOn@ using 'takeWhile':
--
-- @
-- breakOn p = takeWhile (not p)
-- @
--
-- /Pre-release/
--
{-# INLINE takeWhile #-}
takeWhile :: MonadCatch m => (a -> Bool) -> Fold m a b -> Parser m a b
takeWhile :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Fold m a b -> Parser m a b
takeWhile a -> Bool
cond = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
Monad m =>
(a -> Bool) -> Fold m a b -> Parser m a b
D.takeWhile a -> Bool
cond

-- | Like 'takeWhile' but takes at least one element otherwise fails.
--
-- /Pre-release/
--
{-# INLINE takeWhile1 #-}
takeWhile1 :: MonadCatch m => (a -> Bool) -> Fold m a b -> Parser m a b
takeWhile1 :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Fold m a b -> Parser m a b
takeWhile1 a -> Bool
cond = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadThrow m =>
(a -> Bool) -> Fold m a b -> Parser m a b
D.takeWhile1 a -> Bool
cond

-- | Drain the input as long as the predicate succeeds, running the effects and
-- discarding the results.
--
-- This is also called @skipWhile@ in some parsing libraries.
--
-- /Pre-release/
--
{-# INLINE drainWhile #-}
drainWhile :: MonadCatch m => (a -> Bool) -> Parser m a ()
drainWhile :: forall (m :: * -> *) a.
MonadCatch m =>
(a -> Bool) -> Parser m a ()
drainWhile a -> Bool
p = forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Fold m a b -> Parser m a b
takeWhile a -> Bool
p forall (m :: * -> *) a. Monad m => Fold m a ()
FL.drain

-- | @sliceSepByP cond parser@ parses a slice of the input using @parser@ until
-- @cond@ succeeds or the parser stops.
--
-- This is a generalized slicing parser which can be used to implement other
-- parsers e.g.:
--
-- @
-- sliceSepByMax cond n p = sliceSepByP cond (take n p)
-- sliceSepByBetween cond m n p = sliceSepByP cond (takeBetween m n p)
-- @
--
-- /Pre-release/
--
{-# INLINE sliceSepByP #-}
sliceSepByP ::
    MonadCatch m =>
    (a -> Bool) -> Parser m a b -> Parser m a b
sliceSepByP :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Parser m a b -> Parser m a b
sliceSepByP a -> Bool
cond = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Parser m a b -> Parser m a b
D.sliceSepByP a -> Bool
cond forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK

-- | Like 'sliceSepBy' but does not drop the separator element, instead
-- separator is emitted as a separate element in the output.
--
-- /Unimplemented/
{-# INLINE sliceSepWith #-}
sliceSepWith :: -- MonadCatch m =>
    (a -> Bool) -> Fold m a b -> Parser m a b
sliceSepWith :: forall a (m :: * -> *) b. (a -> Bool) -> Fold m a b -> Parser m a b
sliceSepWith a -> Bool
_cond = forall a. HasCallStack => a
undefined -- K.toParserK . D.sliceSepBy cond

-- | Collect stream elements until an elements passes the predicate, return the
-- last element on which the predicate succeeded back to the input stream.  If
-- the predicate succeeds on the first element itself then the parser does not
-- terminate there. The succeeding element in the leading position
-- is treated as a prefix separator which is kept in the output segment.
--
-- * Stops - when the predicate succeeds in non-leading position.
-- * Fails - never.
--
-- S.splitWithPrefix pred f = S.parseMany (PR.sliceBeginWith pred f)
--
-- Examples: -
--
-- >>> :{
--  sliceBeginWithOdd ls = Stream.parse prsr (Stream.fromList ls)
--      where prsr = Parser.sliceBeginWith odd Fold.toList
-- :}
--
--
-- >>> sliceBeginWithOdd [2, 4, 6, 3]
-- *** Exception: sliceBeginWith : slice begins with an element which fails the predicate
-- ...
--
-- >>> sliceBeginWithOdd [3, 5, 7, 4]
-- [3]
--
-- >>> sliceBeginWithOdd [3, 4, 6, 8, 5]
-- [3,4,6,8]
--
-- >>> sliceBeginWithOdd []
-- []
--
-- /Pre-release/
--
{-# INLINE sliceBeginWith #-}
sliceBeginWith ::
    MonadCatch m =>
    (a -> Bool) -> Fold m a b -> Parser m a b
sliceBeginWith :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Fold m a b -> Parser m a b
sliceBeginWith a -> Bool
cond = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
Monad m =>
(a -> Bool) -> Fold m a b -> Parser m a b
D.sliceBeginWith a -> Bool
cond

-- | Like 'sliceSepBy' but the separator elements can be escaped using an
-- escape char determined by the second predicate.
--
-- /Unimplemented/
{-# INLINE escapedSliceSepBy #-}
escapedSliceSepBy :: -- MonadCatch m =>
    (a -> Bool) -> (a -> Bool) -> Fold m a b -> Parser m a b
escapedSliceSepBy :: forall a (m :: * -> *) b.
(a -> Bool) -> (a -> Bool) -> Fold m a b -> Parser m a b
escapedSliceSepBy a -> Bool
_cond a -> Bool
_esc = forall a. HasCallStack => a
undefined
    -- K.toParserK . D.escapedSliceSepBy cond esc

-- | @escapedFrameBy begin end escape@ parses a string framed using @begin@ and
-- @end@ as the frame begin and end marker elements and @escape@ as an escaping
-- element to escape the occurrence of the framing elements within the frame.
-- Nested frames are allowed, but nesting is removed when parsing.
--
-- For example,
--
-- @
-- > Stream.parse (Parser.escapedFrameBy (== '{') (== '}') (== '\\') Fold.toList) $ Stream.fromList "{hello}"
-- "hello"
--
-- > Stream.parse (Parser.escapedFrameBy (== '{') (== '}') (== '\\') Fold.toList) $ Stream.fromList "{hello {world}}"
-- "hello world"
--
-- > Stream.parse (Parser.escapedFrameBy (== '{') (== '}') (== '\\') Fold.toList) $ Stream.fromList "{hello \\{world\\}}"
-- "hello {world}"
--
-- > Stream.parse (Parser.escapedFrameBy (== '{') (== '}') (== '\\') Fold.toList) $ Stream.fromList "{hello {world}"
-- ParseError "Unterminated '{'"
--
-- @
--
-- /Unimplemented/
{-# INLINE escapedFrameBy #-}
escapedFrameBy :: -- MonadCatch m =>
    (a -> Bool) -> (a -> Bool) -> (a -> Bool) -> Fold m a b -> Parser m a b
escapedFrameBy :: forall a (m :: * -> *) b.
(a -> Bool)
-> (a -> Bool) -> (a -> Bool) -> Fold m a b -> Parser m a b
escapedFrameBy a -> Bool
_begin a -> Bool
_end a -> Bool
_escape Fold m a b
_p = forall a. HasCallStack => a
undefined
    -- K.toParserK . D.frameBy begin end escape p

-- | Like 'splitOn' but strips leading, trailing, and repeated separators.
-- Therefore, @".a..b."@ having '.' as the separator would be parsed as
-- @["a","b"]@.  In other words, its like parsing words from whitespace
-- separated text.
--
-- * Stops - when it finds a word separator after a non-word element
-- * Fails - never.
--
-- @
-- S.wordsBy pred f = S.parseMany (PR.wordBy pred f)
-- @
--
{-# INLINE wordBy #-}
wordBy :: MonadCatch m => (a -> Bool) -> Fold m a b -> Parser m a b
wordBy :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> Bool) -> Fold m a b -> Parser m a b
wordBy a -> Bool
f = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
Monad m =>
(a -> Bool) -> Fold m a b -> Parser m a b
D.wordBy a -> Bool
f

-- | Given an input stream @[a,b,c,...]@ and a comparison function @cmp@, the
-- parser assigns the element @a@ to the first group, then if @a \`cmp` b@ is
-- 'True' @b@ is also assigned to the same group.  If @a \`cmp` c@ is 'True'
-- then @c@ is also assigned to the same group and so on. When the comparison
-- fails the parser is terminated. Each group is folded using the 'Fold' @f@ and
-- the result of the fold is the result of the parser.
--
-- * Stops - when the comparison fails.
-- * Fails - never.
--
-- >>> :{
--  runGroupsBy eq =
--      Stream.toList
--          . Stream.parseMany (Parser.groupBy eq Fold.toList)
--          . Stream.fromList
-- :}
--
-- >>> runGroupsBy (<) []
-- []
--
-- >>> runGroupsBy (<) [1]
-- [[1]]
--
-- >>> runGroupsBy (<) [3, 5, 4, 1, 2, 0]
-- [[3,5,4],[1,2],[0]]
--
-- /Pre-release/
--
{-# INLINE groupBy #-}
groupBy :: MonadCatch m => (a -> a -> Bool) -> Fold m a b -> Parser m a b
groupBy :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> a -> Bool) -> Fold m a b -> Parser m a b
groupBy a -> a -> Bool
eq = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
Monad m =>
(a -> a -> Bool) -> Fold m a b -> Parser m a b
D.groupBy a -> a -> Bool
eq

-- | Unlike 'groupBy' this combinator performs a rolling comparison of two
-- successive elements in the input stream.  Assuming the input stream to the
-- parser is @[a,b,c,...]@ and the comparison function is @cmp@, the parser
-- first assigns the element @a@ to the first group, then if @a \`cmp` b@ is
-- 'True' @b@ is also assigned to the same group.  If @b \`cmp` c@ is 'True'
-- then @c@ is also assigned to the same group and so on. When the comparison
-- fails the parser is terminated. Each group is folded using the 'Fold' @f@ and
-- the result of the fold is the result of the parser.
--
-- * Stops - when the comparison fails.
-- * Fails - never.
--
-- >>> :{
--  runGroupsByRolling eq =
--      Stream.toList
--          . Stream.parseMany (Parser.groupByRolling eq Fold.toList)
--          . Stream.fromList
-- :}
--
-- >>> runGroupsByRolling (<) []
-- []
--
-- >>> runGroupsByRolling (<) [1]
-- [[1]]
--
-- >>> runGroupsByRolling (<) [3, 5, 4, 1, 2, 0]
-- [[3,5],[4],[1,2],[0]]
--
-- /Pre-release/
--
{-# INLINE groupByRolling #-}
groupByRolling :: MonadCatch m => (a -> a -> Bool) -> Fold m a b -> Parser m a b
groupByRolling :: forall (m :: * -> *) a b.
MonadCatch m =>
(a -> a -> Bool) -> Fold m a b -> Parser m a b
groupByRolling a -> a -> Bool
eq = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b.
Monad m =>
(a -> a -> Bool) -> Fold m a b -> Parser m a b
D.groupByRolling a -> a -> Bool
eq

-- | Like 'groupByRolling', but if the predicate is 'True' then collects using
-- the first fold as long as the predicate holds 'True', if the predicate is
-- 'False' collects using the second fold as long as it remains 'False'.
-- Returns 'Left' for the first case and 'Right' for the second case.
--
-- For example, if we want to detect sorted sequences in a stream, both
-- ascending and descending cases we can use 'groupByRollingEither (<=)
-- Fold.toList Fold.toList'.
--
-- /Unimplemented/
{-# INLINE groupByRollingEither #-}
groupByRollingEither :: MonadCatch m =>
    (a -> a -> Bool) -> Fold m a b -> Fold m a c -> Parser m a (Either b c)
groupByRollingEither :: forall (m :: * -> *) a b c.
MonadCatch m =>
(a -> a -> Bool)
-> Fold m a b -> Fold m a c -> Parser m a (Either b c)
groupByRollingEither a -> a -> Bool
eq Fold m a b
f1 = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a b c.
MonadCatch m =>
(a -> a -> Bool)
-> Fold m a b -> Fold m a c -> Parser m a (Either b c)
D.groupByRollingEither a -> a -> Bool
eq Fold m a b
f1

-- | Match the given sequence of elements using the given comparison function.
--
-- >>> Stream.parse (Parser.eqBy (==) "string") $ Stream.fromList "string"
--
-- >>> Stream.parse (Parser.eqBy (==) "mismatch") $ Stream.fromList "match"
-- *** Exception: ParseError "eqBy: failed, yet to match 7 elements"
--
-- /Pre-release/
--
{-# INLINE eqBy #-}
eqBy :: MonadCatch m => (a -> a -> Bool) -> [a] -> Parser m a ()
eqBy :: forall (m :: * -> *) a.
MonadCatch m =>
(a -> a -> Bool) -> [a] -> Parser m a ()
eqBy a -> a -> Bool
cmp = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (m :: * -> *) a.
MonadThrow m =>
(a -> a -> Bool) -> [a] -> Parser m a ()
D.eqBy a -> a -> Bool
cmp

-------------------------------------------------------------------------------
-- nested parsers
-------------------------------------------------------------------------------

-- | Sequential parser application. Apply two parsers sequentially to an input
-- stream.  The input is provided to the first parser, when it is done the
-- remaining input is provided to the second parser. If both the parsers
-- succeed their outputs are combined using the supplied function. The
-- operation fails if any of the parsers fail.
--
-- Note: This is a parsing dual of appending streams using
-- 'Streamly.Prelude.serial', it splits the streams using two parsers and zips
-- the results.
--
-- This implementation is strict in the second argument, therefore, the
-- following will fail:
--
-- >>> Stream.parse (Parser.serialWith const (Parser.satisfy (> 0)) undefined) $ Stream.fromList [1]
-- *** Exception: Prelude.undefined
-- ...
--
-- Compare with 'Applicative' instance method '<*>'. This implementation allows
-- stream fusion but has quadratic complexity. This can fuse with other
-- operations and can be faster than 'Applicative' instance for small number
-- (less than 8) of compositions.
--
-- Many combinators can be expressed using @serialWith@ and other parser
-- primitives. Some common idioms are described below,
--
-- @
-- span :: (a -> Bool) -> Fold m a b -> Fold m a b -> Parser m a b
-- span pred f1 f2 = serialWith (,) ('takeWhile' pred f1) ('fromFold' f2)
-- @
--
-- @
-- spanBy :: (a -> a -> Bool) -> Fold m a b -> Fold m a b -> Parser m a b
-- spanBy eq f1 f2 = serialWith (,) ('groupBy' eq f1) ('fromFold' f2)
-- @
--
-- @
-- spanByRolling :: (a -> a -> Bool) -> Fold m a b -> Fold m a b -> Parser m a b
-- spanByRolling eq f1 f2 = serialWith (,) ('groupByRolling' eq f1) ('fromFold' f2)
-- @
--
-- /Pre-release/
--
{-# INLINE serialWith #-}
serialWith :: MonadCatch m
    => (a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
serialWith :: forall (m :: * -> *) a b c x.
MonadCatch m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
serialWith a -> b -> c
f Parser m x a
p1 Parser m x b
p2 =
    forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b c x.
MonadThrow m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
D.serialWith a -> b -> c
f (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x b
p2)

-- | Sequential parser application ignoring the output of the first parser.
-- Apply two parsers sequentially to an input stream.  The input is provided to
-- the first parser, when it is done the remaining input is provided to the
-- second parser. The output of the parser is the output of the second parser.
-- The operation fails if any of the parsers fail.
--
-- This implementation is strict in the second argument, therefore, the
-- following will fail:
--
-- >>> Stream.parse (Parser.split_ (Parser.satisfy (> 0)) undefined) $ Stream.fromList [1]
-- *** Exception: Prelude.undefined
-- ...
--
-- Compare with 'Applicative' instance method '*>'. This implementation allows
-- stream fusion but has quadratic complexity. This can fuse with other
-- operations, and can be faster than 'Applicative' instance for small
-- number (less than 8) of compositions.
--
-- /Pre-release/
--
{-# INLINE split_ #-}
split_ :: MonadCatch m => Parser m x a -> Parser m x b -> Parser m x b
split_ :: forall (m :: * -> *) x a b.
MonadCatch m =>
Parser m x a -> Parser m x b -> Parser m x b
split_ Parser m x a
p1 Parser m x b
p2 = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) x a b.
MonadThrow m =>
Parser m x a -> Parser m x b -> Parser m x b
D.split_ (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x b
p2)

-- | @teeWith f p1 p2@ distributes its input to both @p1@ and @p2@ until both
-- of them succeed or anyone of them fails and combines their output using @f@.
-- The parser succeeds if both the parsers succeed.
--
-- /Pre-release/
--
{-# INLINE teeWith #-}
teeWith :: MonadCatch m
    => (a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
teeWith :: forall (m :: * -> *) a b c x.
MonadCatch m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
teeWith a -> b -> c
f Parser m x a
p1 Parser m x b
p2 =
    forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b c x.
Monad m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
D.teeWith a -> b -> c
f (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x b
p2)

-- | Like 'teeWith' but ends parsing and zips the results, if available,
-- whenever the first parser ends.
--
-- /Pre-release/
--
{-# INLINE teeWithFst #-}
teeWithFst :: MonadCatch m
    => (a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
teeWithFst :: forall (m :: * -> *) a b c x.
MonadCatch m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
teeWithFst a -> b -> c
f Parser m x a
p1 Parser m x b
p2 =
    forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b c x.
Monad m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
D.teeWithFst a -> b -> c
f (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x b
p2)

-- | Like 'teeWith' but ends parsing and zips the results, if available,
-- whenever any of the parsers ends or fails.
--
-- /Unimplemented/
--
{-# INLINE teeWithMin #-}
teeWithMin :: MonadCatch m
    => (a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
teeWithMin :: forall (m :: * -> *) a b c x.
MonadCatch m =>
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
teeWithMin a -> b -> c
f Parser m x a
p1 Parser m x b
p2 =
    forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall a b c (m :: * -> *) x.
(a -> b -> c) -> Parser m x a -> Parser m x b -> Parser m x c
D.teeWithMin a -> b -> c
f (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x b
p2)

-- | Sequential alternative. Apply the input to the first parser and return the
-- result if the parser succeeds. If the first parser fails then backtrack and
-- apply the same input to the second parser and return the result.
--
-- Note: This implementation is not lazy in the second argument. The following
-- will fail:
--
-- >>> Stream.parse (Parser.satisfy (> 0) `Parser.alt` undefined) $ Stream.fromList [1..10]
-- 1
--
-- Compare with 'Alternative' instance method '<|>'. This implementation allows
-- stream fusion but has quadratic complexity. This can fuse with other
-- operations and can be much faster than 'Alternative' instance for small
-- number (less than 8) of alternatives.
--
-- /Pre-release/
--
{-# INLINE alt #-}
alt :: MonadCatch m => Parser m x a -> Parser m x a -> Parser m x a
alt :: forall (m :: * -> *) x a.
MonadCatch m =>
Parser m x a -> Parser m x a -> Parser m x a
alt Parser m x a
p1 Parser m x a
p2 = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) x a.
Monad m =>
Parser m x a -> Parser m x a -> Parser m x a
D.alt (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p2)

-- | Shortest alternative. Apply both parsers in parallel but choose the result
-- from the one which consumed least input i.e. take the shortest succeeding
-- parse.
--
-- /Pre-release/
--
{-# INLINE shortest #-}
shortest :: MonadCatch m
    => Parser m x a -> Parser m x a -> Parser m x a
shortest :: forall (m :: * -> *) x a.
MonadCatch m =>
Parser m x a -> Parser m x a -> Parser m x a
shortest Parser m x a
p1 Parser m x a
p2 = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) x a.
Monad m =>
Parser m x a -> Parser m x a -> Parser m x a
D.shortest (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p2)

-- | Longest alternative. Apply both parsers in parallel but choose the result
-- from the one which consumed more input i.e. take the longest succeeding
-- parse.
--
-- /Pre-release/
--
{-# INLINE longest #-}
longest :: MonadCatch m
    => Parser m x a -> Parser m x a -> Parser m x a
longest :: forall (m :: * -> *) x a.
MonadCatch m =>
Parser m x a -> Parser m x a -> Parser m x a
longest Parser m x a
p1 Parser m x a
p2 = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) x a.
MonadCatch m =>
Parser m x a -> Parser m x a -> Parser m x a
D.longest (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m x a
p2)

-- | Run a parser without consuming the input.
--
-- /Pre-release/
--
{-# INLINE lookAhead #-}
lookAhead :: MonadCatch m => Parser m a b -> Parser m a b
lookAhead :: forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
lookAhead Parser m a b
p = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
D.lookAhead forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p

-- | Takes at-most @n@ input elements.
--
-- * Stops - when the collecting parser stops.
-- * Fails - when the collecting parser fails.
--
-- >>> Stream.parse (Parser.takeP 4 (Parser.takeEQ 2 Fold.toList)) $ Stream.fromList [1, 2, 3, 4, 5]
-- [1,2]
--
-- >>> Stream.parse (Parser.takeP 4 (Parser.takeEQ 5 Fold.toList)) $ Stream.fromList [1, 2, 3, 4, 5]
-- *** Exception: ParseError "takeEQ: Expecting exactly 5 elements, input terminated on 4"
--
-- /Internal/
{-# INLINE takeP #-}
takeP :: MonadCatch m => Int -> Parser m a b -> Parser m a b
takeP :: forall (m :: * -> *) a b.
MonadCatch m =>
Int -> Parser m a b -> Parser m a b
takeP Int
i Parser m a b
p = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b.
Monad m =>
Int -> Parser m a b -> Parser m a b
D.takeP Int
i forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p

-------------------------------------------------------------------------------
-- Interleaving
-------------------------------------------------------------------------------
--
-- To deinterleave we can chain two parsers one behind the other. The input is
-- given to the first parser and the input definitively rejected by the first
-- parser is given to the second parser.
--
-- We can either have the parsers themselves buffer the input or use the shared
-- global buffer to hold it until none of the parsers need it. When the first
-- parser returns Skip (i.e. rewind) we let the second parser consume the
-- rejected input and when it is done we move the cursor forward to the first
-- parser again. This will require a "move forward" command as well.
--
-- To implement grep we can use three parsers, one to find the pattern, one
-- to store the context behind the pattern and one to store the context in
-- front of the pattern. When a match occurs we need to emit the accumulator of
-- all the three parsers. One parser can count the line numbers to provide the
-- line number info.
--
-- | Apply two parsers alternately to an input stream. The input stream is
-- considered an interleaving of two patterns. The two parsers represent the
-- two patterns.
--
-- This undoes a "gintercalate" of two streams.
--
-- /Unimplemented/
--
{-# INLINE deintercalate #-}
deintercalate ::
    -- Monad m =>
       Fold m a y -> Parser m x a
    -> Fold m b z -> Parser m x b
    -> Parser m x (y, z)
deintercalate :: forall (m :: * -> *) a y x b z.
Fold m a y
-> Parser m x a -> Fold m b z -> Parser m x b -> Parser m x (y, z)
deintercalate = forall a. HasCallStack => a
undefined

-------------------------------------------------------------------------------
-- Sequential Collection
-------------------------------------------------------------------------------
--
-- | @concatSequence f t@ collects sequential parses of parsers in the
-- container @t@ using the fold @f@. Fails if the input ends or any of the
-- parsers fail.
--
-- This is same as 'Data.Traversable.sequence' but more efficient.
--
-- /Unimplemented/
--
{-# INLINE concatSequence #-}
concatSequence ::
    -- Foldable t =>
    Fold m b c -> t (Parser m a b) -> Parser m a c
concatSequence :: forall (m :: * -> *) b c (t :: * -> *) a.
Fold m b c -> t (Parser m a b) -> Parser m a c
concatSequence Fold m b c
_f t (Parser m a b)
_p = forall a. HasCallStack => a
undefined

-- | Map a 'Parser' returning function on the result of a 'Parser'.
--
-- Compare with 'Monad' instance method '>>='. This implementation allows
-- stream fusion but has quadratic complexity. This can fuse with other
-- operations and can be much faster than 'Monad' instance for small number
-- (less than 8) of compositions.
--
-- /Pre-release/
--
{-# INLINE concatMap #-}
concatMap :: MonadCatch m
    => (b -> Parser m a c) -> Parser m a b -> Parser m a c
concatMap :: forall (m :: * -> *) b a c.
MonadCatch m =>
(b -> Parser m a c) -> Parser m a b -> Parser m a c
concatMap b -> Parser m a c
f Parser m a b
p = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) b a c.
MonadThrow m =>
(b -> Parser m a c) -> Parser m a b -> Parser m a c
D.concatMap (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK forall b c a. (b -> c) -> (a -> b) -> a -> c
. b -> Parser m a c
f) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p)

-------------------------------------------------------------------------------
-- Alternative Collection
-------------------------------------------------------------------------------
--
-- | @choice parsers@ applies the @parsers@ in order and returns the first
-- successful parse.
--
-- This is same as 'asum' but more efficient.
--
-- /Broken/
--
{-# INLINE choice #-}
choice ::
       (Functor t, Foldable t, MonadCatch m) => t (Parser m a b) -> Parser m a b
choice :: forall (t :: * -> *) (m :: * -> *) a b.
(Functor t, Foldable t, MonadCatch m) =>
t (Parser m a b) -> Parser m a b
choice t (Parser m a b)
ps = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) (t :: * -> *) a b.
(MonadCatch m, Foldable t) =>
t (Parser m a b) -> Parser m a b
D.choice forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> t (Parser m a b)
ps

-------------------------------------------------------------------------------
-- Sequential Repetition
-------------------------------------------------------------------------------
--
-- $many
-- TODO "many" is essentially a Fold because it cannot fail. So it can be
-- downgraded to a Fold. Or we can make the return type a Fold instead and
-- upgrade that to a parser when needed.

-- | Like 'many' but uses a 'Parser' instead of a 'Fold' to collect the
-- results. Parsing stops or fails if the collecting parser stops or fails.
--
-- /Unimplemented/
--
{-# INLINE manyP #-}
manyP :: -- MonadCatch m =>
    Parser m a b -> Parser m b c -> Parser m a c
manyP :: forall (m :: * -> *) a b c.
Parser m a b -> Parser m b c -> Parser m a c
manyP Parser m a b
_p Parser m b c
_f = forall a. HasCallStack => a
undefined -- K.toParserK $ D.manyP (K.fromParserK p) f

-- | Collect zero or more parses. Apply the supplied parser repeatedly on the
-- input stream and push the parse results to a downstream fold.
--
--  Stops: when the downstream fold stops or the parser fails.
--  Fails: never, produces zero or more results.
--
-- Compare with 'Control.Applicative.many'.
--
-- /Pre-release/
--
{-# INLINE many #-}
many :: MonadCatch m => Parser m a b -> Fold m b c -> Parser m a c
many :: forall (m :: * -> *) a b c.
MonadCatch m =>
Parser m a b -> Fold m b c -> Parser m a c
many Parser m a b
p Fold m b c
f = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b c.
MonadCatch m =>
Parser m a b -> Fold m b c -> Parser m a c
D.many (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p) Fold m b c
f
-- many = countBetween 0 maxBound

-- Note: many1 would perhaps be a better name for this and consistent with
-- other names like takeWhile1. But we retain the name "some" for
-- compatibility.
--
-- | Collect one or more parses. Apply the supplied parser repeatedly on the
-- input stream and push the parse results to a downstream fold.
--
--  Stops: when the downstream fold stops or the parser fails.
--  Fails: if it stops without producing a single result.
--
-- @some fld parser = manyP (takeGE 1 fld) parser@
--
-- Compare with 'Control.Applicative.some'.
--
-- /Pre-release/
--
{-# INLINE some #-}
some :: MonadCatch m => Parser m a b -> Fold m b c -> Parser m a c
some :: forall (m :: * -> *) a b c.
MonadCatch m =>
Parser m a b -> Fold m b c -> Parser m a c
some Parser m a b
p Fold m b c
f = forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) a b c.
MonadCatch m =>
Parser m a b -> Fold m b c -> Parser m a c
D.some (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p) Fold m b c
f
-- some p f = manyP p (takeGE 1 f)
-- many = countBetween 1 maxBound

-- | @countBetween m n f p@ collects between @m@ and @n@ sequential parses of
-- parser @p@ using the fold @f@. Stop after collecting @n@ results. Fails if
-- the input ends or the parser fails before @m@ results are collected.
--
-- /Unimplemented/
--
{-# INLINE countBetween #-}
countBetween ::
    -- MonadCatch m =>
    Int -> Int -> Parser m a b -> Fold m b c -> Parser m a c
countBetween :: forall (m :: * -> *) a b c.
Int -> Int -> Parser m a b -> Fold m b c -> Parser m a c
countBetween Int
_m Int
_n Parser m a b
_p = forall a. HasCallStack => a
undefined
-- countBetween m n p f = manyP (takeBetween m n f) p

-- | @count n f p@ collects exactly @n@ sequential parses of parser @p@ using
-- the fold @f@.  Fails if the input ends or the parser fails before @n@
-- results are collected.
--
-- /Unimplemented/
--
{-# INLINE count #-}
count ::
    -- MonadCatch m =>
    Int -> Parser m a b -> Fold m b c -> Parser m a c
count :: forall (m :: * -> *) a b c.
Int -> Parser m a b -> Fold m b c -> Parser m a c
count Int
n = forall (m :: * -> *) a b c.
Int -> Int -> Parser m a b -> Fold m b c -> Parser m a c
countBetween Int
n Int
n
-- count n p f = manyP (takeEQ n f) p

-- | Like 'manyTill' but uses a 'Parser' to collect the results instead of a
-- 'Fold'.  Parsing stops or fails if the collecting parser stops or fails.
--
-- We can implemnent parsers like the following using 'manyTillP':
--
-- @
-- countBetweenTill m n f p = manyTillP (takeBetween m n f) p
-- @
--
-- /Unimplemented/
--
{-# INLINE manyTillP #-}
manyTillP :: -- MonadCatch m =>
    Parser m a b -> Parser m a x -> Parser m b c -> Parser m a c
manyTillP :: forall (m :: * -> *) a b x c.
Parser m a b -> Parser m a x -> Parser m b c -> Parser m a c
manyTillP Parser m a b
_p1 Parser m a x
_p2 Parser m b c
_f = forall a. HasCallStack => a
undefined
    -- K.toParserK $ D.manyTillP (K.fromParserK p1) (K.fromParserK p2) f

-- | @manyTill f collect test@ tries the parser @test@ on the input, if @test@
-- fails it backtracks and tries @collect@, after @collect@ succeeds @test@ is
-- tried again and so on. The parser stops when @test@ succeeds.  The output of
-- @test@ is discarded and the output of @collect@ is accumulated by the
-- supplied fold. The parser fails if @collect@ fails.
--
-- Stops when the fold @f@ stops.
--
-- /Pre-release/
--
{-# INLINE manyTill #-}
manyTill :: MonadCatch m
    => Parser m a b -> Parser m a x -> Fold m b c -> Parser m a c
manyTill :: forall (m :: * -> *) a b x c.
MonadCatch m =>
Parser m a b -> Parser m a x -> Fold m b c -> Parser m a c
manyTill Parser m a b
p1 Parser m a x
p2 Fold m b c
f =
    forall (m :: * -> *) a b.
MonadCatch m =>
Parser m a b -> Parser m a b
K.toParserK forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *) b c a x.
MonadCatch m =>
Fold m b c -> Parser m a b -> Parser m a x -> Parser m a c
D.manyTill Fold m b c
f (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a b
p1) (forall (m :: * -> *) a b.
MonadThrow m =>
Parser m a b -> Parser m a b
K.fromParserK Parser m a x
p2)

-- | @manyThen f collect recover@ repeats the parser @collect@ on the input and
-- collects the output in the supplied fold. If the the parser @collect@ fails,
-- parser @recover@ is run until it stops and then we start repeating the
-- parser @collect@ again. The parser fails if the recovery parser fails.
--
-- For example, this can be used to find a key frame in a video stream after an
-- error.
--
-- /Unimplemented/
--
{-# INLINE manyThen #-}
manyThen :: -- (Foldable t, MonadCatch m) =>
    Parser m a b -> Parser m a x -> Fold m b c -> Parser m a c
manyThen :: forall (m :: * -> *) a b x c.
Parser m a b -> Parser m a x -> Fold m b c -> Parser m a c
manyThen Parser m a b
_parser Parser m a x
_recover Fold m b c
_f = forall a. HasCallStack => a
undefined

-------------------------------------------------------------------------------
-- Interleaving a collection of parsers
-------------------------------------------------------------------------------
--
-- | Apply a collection of parsers to an input stream in a round robin fashion.
-- Each parser is applied until it stops and then we repeat starting with the
-- the first parser again.
--
-- /Unimplemented/
--
{-# INLINE roundRobin #-}
roundRobin :: -- (Foldable t, MonadCatch m) =>
    t (Parser m a b) -> Fold m b c -> Parser m a c
roundRobin :: forall (t :: * -> *) (m :: * -> *) a b c.
t (Parser m a b) -> Fold m b c -> Parser m a c
roundRobin t (Parser m a b)
_ps Fold m b c
_f = forall a. HasCallStack => a
undefined

-------------------------------------------------------------------------------
-- Repeated Alternatives
-------------------------------------------------------------------------------

-- | Keep trying a parser up to a maximum of @n@ failures.  When the parser
-- fails the input consumed till now is dropped and the new instance is tried
-- on the fresh input.
--
-- /Unimplemented/
--
{-# INLINE retryMaxTotal #-}
retryMaxTotal :: -- (MonadCatch m) =>
    Int -> Parser m a b -> Fold m b c -> Parser m a c
retryMaxTotal :: forall (m :: * -> *) a b c.
Int -> Parser m a b -> Fold m b c -> Parser m a c
retryMaxTotal Int
_n Parser m a b
_p Fold m b c
_f  = forall a. HasCallStack => a
undefined

-- | Like 'retryMaxTotal' but aborts after @n@ successive failures.
--
-- /Unimplemented/
--
{-# INLINE retryMaxSuccessive #-}
retryMaxSuccessive :: -- (MonadCatch m) =>
    Int -> Parser m a b -> Fold m b c -> Parser m a c
retryMaxSuccessive :: forall (m :: * -> *) a b c.
Int -> Parser m a b -> Fold m b c -> Parser m a c
retryMaxSuccessive Int
_n Parser m a b
_p Fold m b c
_f = forall a. HasCallStack => a
undefined

-- | Keep trying a parser until it succeeds.  When the parser fails the input
-- consumed till now is dropped and the new instance is tried on the fresh
-- input.
--
-- /Unimplemented/
--
{-# INLINE retry #-}
retry :: -- (MonadCatch m) =>
    Parser m a b -> Parser m a b
retry :: forall (m :: * -> *) a b. Parser m a b -> Parser m a b
retry Parser m a b
_p = forall a. HasCallStack => a
undefined