{-# LANGUAGE CPP, FlexibleContexts, Safe #-}

-----------------------------------------------------------------------------
-- |
-- Module      :  Text.Parsec.Char
-- Copyright   :  (c) Daan Leijen 1999-2001, (c) Paolo Martini 2007
-- License     :  BSD-style (see the LICENSE file)
--
-- Maintainer  :  derek.a.elkins@gmail.com
-- Stability   :  provisional
-- Portability :  portable
--
-- Commonly used character parsers.
--
-----------------------------------------------------------------------------

module Text.Parsec.Char where

import Data.Char
import Text.Parsec.Pos
import Text.Parsec.Prim
#if !(MIN_VERSION_base(4,8,0))
import Control.Applicative ((*>))
#endif

-- | @oneOf cs@ succeeds if the current character is in the supplied
-- list of characters @cs@. Returns the parsed character. See also
-- 'satisfy'.
--
-- >   vowel  = oneOf "aeiou"

oneOf :: (Stream s m Char) => [Char] -> ParsecT s u m Char
oneOf :: [Char] -> ParsecT s u m Char
oneOf [Char]
cs            = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy (\Char
c -> Char -> [Char] -> Bool
forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
elem Char
c [Char]
cs)

-- | As the dual of 'oneOf', @noneOf cs@ succeeds if the current
-- character /not/ in the supplied list of characters @cs@. Returns the
-- parsed character.
--
-- >  consonant = noneOf "aeiou"

noneOf :: (Stream s m Char) => [Char] -> ParsecT s u m Char
noneOf :: [Char] -> ParsecT s u m Char
noneOf [Char]
cs           = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy (\Char
c -> Bool -> Bool
not (Char -> [Char] -> Bool
forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
elem Char
c [Char]
cs))

-- | Skips /zero/ or more white space characters. See also 'skipMany'.

spaces :: (Stream s m Char) => ParsecT s u m ()
spaces :: ParsecT s u m ()
spaces              = ParsecT s u m Char -> ParsecT s u m ()
forall s u (m :: * -> *) a. ParsecT s u m a -> ParsecT s u m ()
skipMany ParsecT s u m Char
forall s (m :: * -> *) u. Stream s m Char => ParsecT s u m Char
space        ParsecT s u m () -> [Char] -> ParsecT s u m ()
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"white space"

-- | Parses a white space character (any character which satisfies 'isSpace')
-- Returns the parsed character.

space :: (Stream s m Char) => ParsecT s u m Char
space :: ParsecT s u m Char
space               = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isSpace       ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"space"

-- | Parses a newline character (\'\\n\'). Returns a newline character.

newline :: (Stream s m Char) => ParsecT s u m Char
newline :: ParsecT s u m Char
newline             = Char -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
Char -> ParsecT s u m Char
char Char
'\n'             ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"lf new-line"

-- | Parses a carriage return character (\'\\r\') followed by a newline character (\'\\n\').
-- Returns a newline character.

crlf :: (Stream s m Char) => ParsecT s u m Char
crlf :: ParsecT s u m Char
crlf                = Char -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
Char -> ParsecT s u m Char
char Char
'\r' ParsecT s u m Char -> ParsecT s u m Char -> ParsecT s u m Char
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> Char -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
Char -> ParsecT s u m Char
char Char
'\n' ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"crlf new-line"

-- | Parses a CRLF (see 'crlf') or LF (see 'newline') end-of-line.
-- Returns a newline character (\'\\n\').
--
-- > endOfLine = newline <|> crlf
--

endOfLine :: (Stream s m Char) => ParsecT s u m Char
endOfLine :: ParsecT s u m Char
endOfLine           = ParsecT s u m Char
forall s (m :: * -> *) u. Stream s m Char => ParsecT s u m Char
newline ParsecT s u m Char -> ParsecT s u m Char -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> ParsecT s u m a -> ParsecT s u m a
<|> ParsecT s u m Char
forall s (m :: * -> *) u. Stream s m Char => ParsecT s u m Char
crlf       ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"new-line"

-- | Parses a tab character (\'\\t\'). Returns a tab character.

tab :: (Stream s m Char) => ParsecT s u m Char
tab :: ParsecT s u m Char
tab                 = Char -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
Char -> ParsecT s u m Char
char Char
'\t'             ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"tab"

-- | Parses an upper case letter (according to 'isUpper').
-- Returns the parsed character.

upper :: (Stream s m Char) => ParsecT s u m Char
upper :: ParsecT s u m Char
upper               = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isUpper       ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"uppercase letter"

-- | Parses a lower case character (according to 'isLower').
-- Returns the parsed character.

lower :: (Stream s m Char) => ParsecT s u m Char
lower :: ParsecT s u m Char
lower               = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isLower       ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"lowercase letter"

-- | Parses a alphabetic or numeric Unicode characters
-- according to 'isAlphaNum'. Returns the parsed character.
--
-- Note that numeric digits outside the ASCII range (such as arabic-indic digits like e.g. \"٤\" or @U+0664@),
-- as well as numeric characters which aren't digits, are parsed by this function
-- but not by 'digit'.

alphaNum :: (Stream s m Char => ParsecT s u m Char)
alphaNum :: ParsecT s u m Char
alphaNum            = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isAlphaNum    ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"letter or digit"

-- | Parses an alphabetic Unicode characters (lower-case, upper-case and title-case letters,
-- plus letters of caseless scripts and modifiers letters according to 'isAlpha').
-- Returns the parsed character.

letter :: (Stream s m Char) => ParsecT s u m Char
letter :: ParsecT s u m Char
letter              = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isAlpha       ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"letter"

-- | Parses an ASCII digit. Returns the parsed character.

digit :: (Stream s m Char) => ParsecT s u m Char
digit :: ParsecT s u m Char
digit               = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isDigit       ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"digit"

-- | Parses a hexadecimal digit (a digit or a letter between \'a\' and
-- \'f\' or \'A\' and \'F\'). Returns the parsed character.

hexDigit :: (Stream s m Char) => ParsecT s u m Char
hexDigit :: ParsecT s u m Char
hexDigit            = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isHexDigit    ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"hexadecimal digit"

-- | Parses an octal digit (a character between \'0\' and \'7\'). Returns
-- the parsed character.

octDigit :: (Stream s m Char) => ParsecT s u m Char
octDigit :: ParsecT s u m Char
octDigit            = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
isOctDigit    ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char]
"octal digit"

-- | @char c@ parses a single character @c@. Returns the parsed
-- character (i.e. @c@).
--
-- >  semiColon  = char ';'

char :: (Stream s m Char) => Char -> ParsecT s u m Char
char :: Char -> ParsecT s u m Char
char Char
c              = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy (Char -> Char -> Bool
forall a. Eq a => a -> a -> Bool
==Char
c)  ParsecT s u m Char -> [Char] -> ParsecT s u m Char
forall s u (m :: * -> *) a.
ParsecT s u m a -> [Char] -> ParsecT s u m a
<?> [Char] -> [Char]
forall a. Show a => a -> [Char]
show [Char
c]

-- | This parser succeeds for any character. Returns the parsed character.

anyChar :: (Stream s m Char) => ParsecT s u m Char
anyChar :: ParsecT s u m Char
anyChar             = (Char -> Bool) -> ParsecT s u m Char
forall s (m :: * -> *) u.
Stream s m Char =>
(Char -> Bool) -> ParsecT s u m Char
satisfy (Bool -> Char -> Bool
forall a b. a -> b -> a
const Bool
True)

-- | The parser @satisfy f@ succeeds for any character for which the
-- supplied function @f@ returns 'True'. Returns the character that is
-- actually parsed.

-- >  digit     = satisfy isDigit
-- >  oneOf cs  = satisfy (\c -> c `elem` cs)

satisfy :: (Stream s m Char) => (Char -> Bool) -> ParsecT s u m Char
satisfy :: (Char -> Bool) -> ParsecT s u m Char
satisfy Char -> Bool
f           = (Char -> [Char])
-> (SourcePos -> Char -> s -> SourcePos)
-> (Char -> Maybe Char)
-> ParsecT s u m Char
forall s (m :: * -> *) t a u.
Stream s m t =>
(t -> [Char])
-> (SourcePos -> t -> s -> SourcePos)
-> (t -> Maybe a)
-> ParsecT s u m a
tokenPrim (\Char
c -> [Char] -> [Char]
forall a. Show a => a -> [Char]
show [Char
c])
                                (\SourcePos
pos Char
c s
_cs -> SourcePos -> Char -> SourcePos
updatePosChar SourcePos
pos Char
c)
                                (\Char
c -> if Char -> Bool
f Char
c then Char -> Maybe Char
forall a. a -> Maybe a
Just Char
c else Maybe Char
forall a. Maybe a
Nothing)

-- | @string s@ parses a sequence of characters given by @s@. Returns
-- the parsed string (i.e. @s@).
--
-- >  divOrMod    =   string "div"
-- >              <|> string "mod"

string :: (Stream s m Char) => String -> ParsecT s u m String
string :: [Char] -> ParsecT s u m [Char]
string [Char]
s            = ([Char] -> [Char])
-> (SourcePos -> [Char] -> SourcePos)
-> [Char]
-> ParsecT s u m [Char]
forall s (m :: * -> *) t u.
(Stream s m t, Eq t) =>
([t] -> [Char])
-> (SourcePos -> [t] -> SourcePos) -> [t] -> ParsecT s u m [t]
tokens [Char] -> [Char]
forall a. Show a => a -> [Char]
show SourcePos -> [Char] -> SourcePos
updatePosString [Char]
s