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Re-export <|> from Applicative, rather than re-defining it #62

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Re-export <|> from Applicative, rather than re-defining it #62

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30 changes: 13 additions & 17 deletions Text/Parsec/Prim.hs
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Original file line number Diff line number Diff line change
Expand Up @@ -35,7 +35,7 @@ module Text.Parsec.Prim
, parserZero
, parserPlus
, (<?>)
, (<|>)
, Applicative.Alternative(empty, (<|>))
, label
, labels
, lookAhead
Expand Down Expand Up @@ -297,6 +297,18 @@ parserZero
= ParsecT $ \s _ _ _ eerr ->
eerr $ unknownError s

-- | This function implements choice. The parser @parserPlus p q@ first
-- applies @p@. If it succeeds, the value of @p@ is returned. If @p@
-- fails /without consuming any input/, parser @q@ is tried. This
-- combinator is defined equal to the 'mplus' member of the 'MonadPlus'
-- class and the ('Control.Applicative.<|>') member of 'Control.Applicative.Alternative'.
--
-- The parser is called /predictive/ since @q@ is only tried when
-- parser @p@ didn't consume any input (i.e.. the look ahead is 1).
-- This non-backtracking behaviour allows for both an efficient
-- implementation of the parser combinators and the generation of good
-- error messages.

parserPlus :: ParsecT s u m a -> ParsecT s u m a -> ParsecT s u m a
{-# INLINE parserPlus #-}
parserPlus m n
Expand All @@ -315,7 +327,6 @@ instance MonadTrans (ParsecT s u) where
eok a s $ unknownError s

infix 0 <?>
infixr 1 <|>

-- | The parser @p \<?> msg@ behaves as parser @p@, but whenever the
-- parser @p@ fails /without consuming any input/, it replaces expect
Expand All @@ -332,21 +343,6 @@ infixr 1 <|>
(<?>) :: (ParsecT s u m a) -> String -> (ParsecT s u m a)
p <?> msg = label p msg

-- | This combinator implements choice. The parser @p \<|> q@ first
-- applies @p@. If it succeeds, the value of @p@ is returned. If @p@
-- fails /without consuming any input/, parser @q@ is tried. This
-- combinator is defined equal to the 'mplus' member of the 'MonadPlus'
-- class and the ('Control.Applicative.<|>') member of 'Control.Applicative.Alternative'.
--
-- The parser is called /predictive/ since @q@ is only tried when
-- parser @p@ didn't consume any input (i.e.. the look ahead is 1).
-- This non-backtracking behaviour allows for both an efficient
-- implementation of the parser combinators and the generation of good
-- error messages.

(<|>) :: (ParsecT s u m a) -> (ParsecT s u m a) -> (ParsecT s u m a)
p1 <|> p2 = mplus p1 p2

-- | A synonym for @\<?>@, but as a function instead of an operator.
label :: ParsecT s u m a -> String -> ParsecT s u m a
label p msg
Expand Down