pandoc/src/Text/Pandoc/Parsing.hs
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{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-
Copyright (C) 2006-2010 John MacFarlane <jgm@berkeley.edu>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-}
{- |
Module : Text.Pandoc.Parsing
Copyright : Copyright (C) 2006-2010 John MacFarlane
License : GNU GPL, version 2 or above
Maintainer : John MacFarlane <jgm@berkeley.edu>
Stability : alpha
Portability : portable
A utility library with parsers used in pandoc readers.
-}
module Text.Pandoc.Parsing ( (>>~),
anyLine,
many1Till,
notFollowedBy',
oneOfStrings,
spaceChar,
nonspaceChar,
skipSpaces,
blankline,
blanklines,
enclosed,
stringAnyCase,
parseFromString,
lineClump,
charsInBalanced,
romanNumeral,
emailAddress,
uri,
withHorizDisplacement,
withRaw,
escaped,
characterReference,
updateLastStrPos,
anyOrderedListMarker,
orderedListMarker,
charRef,
tableWith,
widthsFromIndices,
gridTableWith,
readWith,
testStringWith,
getOption,
guardEnabled,
guardDisabled,
ParserState (..),
defaultParserState,
HeaderType (..),
ParserContext (..),
QuoteContext (..),
NoteTable,
NoteTable',
KeyTable,
SubstTable,
Key (..),
toKey,
smartPunctuation,
withQuoteContext,
singleQuoteStart,
singleQuoteEnd,
doubleQuoteStart,
doubleQuoteEnd,
ellipses,
apostrophe,
dash,
nested,
macro,
applyMacros',
Parser,
F(..),
runF,
askF,
asksF,
-- * Re-exports from Text.Pandoc.Parsec
runParser,
parse,
anyToken,
getInput,
setInput,
unexpected,
char,
letter,
digit,
alphaNum,
skipMany,
skipMany1,
spaces,
space,
anyChar,
satisfy,
newline,
string,
count,
eof,
noneOf,
oneOf,
lookAhead,
notFollowedBy,
many,
many1,
manyTill,
(<|>),
(<?>),
choice,
try,
sepBy,
sepBy1,
sepEndBy,
sepEndBy1,
endBy,
endBy1,
option,
optional,
optionMaybe,
getState,
setState,
updateState,
SourcePos,
getPosition,
setPosition,
sourceColumn,
sourceLine,
newPos,
token
)
where
import Text.Pandoc.Definition
import Text.Pandoc.Options
import Text.Pandoc.Builder (Blocks, Inlines)
import qualified Text.Pandoc.UTF8 as UTF8 (putStrLn)
import Text.Parsec
import Text.Parsec.Pos (newPos)
import Data.Char ( toLower, toUpper, ord, isAscii, isAlphaNum, isDigit, isPunctuation )
import Data.List ( intercalate, transpose )
import Network.URI ( parseURI, URI (..), isAllowedInURI )
import Text.Pandoc.Shared
import qualified Data.Map as M
import Text.TeXMath.Macros (applyMacros, Macro, parseMacroDefinitions)
import Text.HTML.TagSoup.Entity ( lookupEntity )
import Data.Default
import qualified Data.Set as Set
import Control.Monad.Reader
import Data.Monoid
type Parser t s = Parsec t s
newtype F a = F { unF :: Reader ParserState a } deriving (Monad, Functor)
runF :: F a -> ParserState -> a
runF = runReader . unF
askF :: F ParserState
askF = F ask
asksF :: (ParserState -> a) -> F a
asksF f = F $ asks f
instance Monoid a => Monoid (F a) where
mempty = return mempty
mappend = liftM2 mappend
mconcat = liftM mconcat . sequence
-- | Like >>, but returns the operation on the left.
-- (Suggested by Tillmann Rendel on Haskell-cafe list.)
(>>~) :: (Monad m) => m a -> m b -> m a
a >>~ b = a >>= \x -> b >> return x
-- | Parse any line of text
anyLine :: Parser [Char] st [Char]
anyLine = manyTill anyChar newline
-- | Like @manyTill@, but reads at least one item.
many1Till :: Parser [tok] st a
-> Parser [tok] st end
-> Parser [tok] st [a]
many1Till p end = do
first <- p
rest <- manyTill p end
return (first:rest)
-- | A more general form of @notFollowedBy@. This one allows any
-- type of parser to be specified, and succeeds only if that parser fails.
-- It does not consume any input.
notFollowedBy' :: Show b => Parser [a] st b -> Parser [a] st ()
notFollowedBy' p = try $ join $ do a <- try p
return (unexpected (show a))
<|>
return (return ())
-- (This version due to Andrew Pimlott on the Haskell mailing list.)
-- | Parses one of a list of strings (tried in order).
oneOfStrings :: [String] -> Parser [Char] st String
oneOfStrings [] = fail "no strings"
oneOfStrings strs = do
c <- anyChar
let strs' = [xs | (x:xs) <- strs, x == c]
case strs' of
[] -> fail "not found"
z | "" `elem` z -> return [c]
| otherwise -> (c:) `fmap` oneOfStrings strs'
-- | Parses a space or tab.
spaceChar :: Parser [Char] st Char
spaceChar = satisfy $ \c -> c == ' ' || c == '\t'
-- | Parses a nonspace, nonnewline character.
nonspaceChar :: Parser [Char] st Char
nonspaceChar = satisfy $ \x -> x /= '\t' && x /= '\n' && x /= ' ' && x /= '\r'
-- | Skips zero or more spaces or tabs.
skipSpaces :: Parser [Char] st ()
skipSpaces = skipMany spaceChar
-- | Skips zero or more spaces or tabs, then reads a newline.
blankline :: Parser [Char] st Char
blankline = try $ skipSpaces >> newline
-- | Parses one or more blank lines and returns a string of newlines.
blanklines :: Parser [Char] st [Char]
blanklines = many1 blankline
-- | Parses material enclosed between start and end parsers.
enclosed :: Parser [Char] st t -- ^ start parser
-> Parser [Char] st end -- ^ end parser
-> Parser [Char] st a -- ^ content parser (to be used repeatedly)
-> Parser [Char] st [a]
enclosed start end parser = try $
start >> notFollowedBy space >> many1Till parser end
-- | Parse string, case insensitive.
stringAnyCase :: [Char] -> Parser [Char] st String
stringAnyCase [] = string ""
stringAnyCase (x:xs) = do
firstChar <- char (toUpper x) <|> char (toLower x)
rest <- stringAnyCase xs
return (firstChar:rest)
-- | Parse contents of 'str' using 'parser' and return result.
parseFromString :: Parser [tok] st a -> [tok] -> Parser [tok] st a
parseFromString parser str = do
oldPos <- getPosition
oldInput <- getInput
setInput str
result <- parser
setInput oldInput
setPosition oldPos
return result
-- | Parse raw line block up to and including blank lines.
lineClump :: Parser [Char] st String
lineClump = blanklines
<|> (many1 (notFollowedBy blankline >> anyLine) >>= return . unlines)
-- | Parse a string of characters between an open character
-- and a close character, including text between balanced
-- pairs of open and close, which must be different. For example,
-- @charsInBalanced '(' ')' anyChar@ will parse "(hello (there))"
-- and return "hello (there)".
charsInBalanced :: Char -> Char -> Parser [Char] st Char
-> Parser [Char] st String
charsInBalanced open close parser = try $ do
char open
let isDelim c = c == open || c == close
raw <- many $ many1 (notFollowedBy (satisfy isDelim) >> parser)
<|> (do res <- charsInBalanced open close parser
return $ [open] ++ res ++ [close])
char close
return $ concat raw
-- old charsInBalanced would be:
-- charsInBalanced open close (noneOf "\n" <|> char '\n' >> notFollowedBy blankline)
-- old charsInBalanced' would be:
-- charsInBalanced open close anyChar
-- Auxiliary functions for romanNumeral:
lowercaseRomanDigits :: [Char]
lowercaseRomanDigits = ['i','v','x','l','c','d','m']
uppercaseRomanDigits :: [Char]
uppercaseRomanDigits = map toUpper lowercaseRomanDigits
-- | Parses a roman numeral (uppercase or lowercase), returns number.
romanNumeral :: Bool -- ^ Uppercase if true
-> Parser [Char] st Int
romanNumeral upperCase = do
let romanDigits = if upperCase
then uppercaseRomanDigits
else lowercaseRomanDigits
lookAhead $ oneOf romanDigits
let [one, five, ten, fifty, hundred, fivehundred, thousand] =
map char romanDigits
thousands <- many thousand >>= (return . (1000 *) . length)
ninehundreds <- option 0 $ try $ hundred >> thousand >> return 900
fivehundreds <- many fivehundred >>= (return . (500 *) . length)
fourhundreds <- option 0 $ try $ hundred >> fivehundred >> return 400
hundreds <- many hundred >>= (return . (100 *) . length)
nineties <- option 0 $ try $ ten >> hundred >> return 90
fifties <- many fifty >>= (return . (50 *) . length)
forties <- option 0 $ try $ ten >> fifty >> return 40
tens <- many ten >>= (return . (10 *) . length)
nines <- option 0 $ try $ one >> ten >> return 9
fives <- many five >>= (return . (5 *) . length)
fours <- option 0 $ try $ one >> five >> return 4
ones <- many one >>= (return . length)
let total = thousands + ninehundreds + fivehundreds + fourhundreds +
hundreds + nineties + fifties + forties + tens + nines +
fives + fours + ones
if total == 0
then fail "not a roman numeral"
else return total
-- Parsers for email addresses and URIs
emailChar :: Parser [Char] st Char
emailChar = alphaNum <|>
satisfy (\c -> c == '-' || c == '+' || c == '_' || c == '.')
domainChar :: Parser [Char] st Char
domainChar = alphaNum <|> char '-'
domain :: Parser [Char] st [Char]
domain = do
first <- many1 domainChar
dom <- many1 $ try (char '.' >> many1 domainChar )
return $ intercalate "." (first:dom)
-- | Parses an email address; returns original and corresponding
-- escaped mailto: URI.
emailAddress :: Parser [Char] st (String, String)
emailAddress = try $ do
firstLetter <- alphaNum
restAddr <- many emailChar
let addr = firstLetter:restAddr
char '@'
dom <- domain
let full = addr ++ '@':dom
return (full, escapeURI $ "mailto:" ++ full)
-- | Parses a URI. Returns pair of original and URI-escaped version.
uri :: Parser [Char] st (String, String)
uri = try $ do
let protocols = [ "http:", "https:", "ftp:", "file:", "mailto:",
"news:", "telnet:" ]
lookAhead $ oneOfStrings protocols
-- Scan non-ascii characters and ascii characters allowed in a URI.
-- We allow punctuation except when followed by a space, since
-- we don't want the trailing '.' in 'http://google.com.'
let innerPunct = try $ satisfy isPunctuation >>~
notFollowedBy (newline <|> spaceChar)
let uriChar = innerPunct <|>
satisfy (\c -> not (isPunctuation c) &&
(not (isAscii c) || isAllowedInURI c))
-- We want to allow
-- http://en.wikipedia.org/wiki/State_of_emergency_(disambiguation)
-- as a URL, while NOT picking up the closing paren in
-- (http://wikipedia.org)
-- So we include balanced parens in the URL.
let inParens = try $ do char '('
res <- many uriChar
char ')'
return $ '(' : res ++ ")"
str <- liftM concat $ many1 $ inParens <|> count 1 (innerPunct <|> uriChar)
str' <- option str $ char '/' >> return (str ++ "/")
-- now see if they amount to an absolute URI
case parseURI (escapeURI str') of
Just uri' -> if uriScheme uri' `elem` protocols
then return (str', show uri')
else fail "not a URI"
Nothing -> fail "not a URI"
-- | Applies a parser, returns tuple of its results and its horizontal
-- displacement (the difference between the source column at the end
-- and the source column at the beginning). Vertical displacement
-- (source row) is ignored.
withHorizDisplacement :: Parser [Char] st a -- ^ Parser to apply
-> Parser [Char] st (a, Int) -- ^ (result, displacement)
withHorizDisplacement parser = do
pos1 <- getPosition
result <- parser
pos2 <- getPosition
return (result, sourceColumn pos2 - sourceColumn pos1)
-- | Applies a parser and returns the raw string that was parsed,
-- along with the value produced by the parser.
withRaw :: Parser [Char] st a -> Parser [Char] st (a, [Char])
withRaw parser = do
pos1 <- getPosition
inp <- getInput
result <- parser
pos2 <- getPosition
let (l1,c1) = (sourceLine pos1, sourceColumn pos1)
let (l2,c2) = (sourceLine pos2, sourceColumn pos2)
let inplines = take ((l2 - l1) + 1) $ lines inp
let raw = case inplines of
[] -> ""
[l] -> take (c2 - c1) l
ls -> unlines (init ls) ++ take (c2 - 1) (last ls)
return (result, raw)
-- | Parses backslash, then applies character parser.
escaped :: Parser [Char] st Char -- ^ Parser for character to escape
-> Parser [Char] st Char
escaped parser = try $ char '\\' >> parser
-- | Parse character entity.
characterReference :: Parser [Char] st Char
characterReference = try $ do
char '&'
ent <- many1Till nonspaceChar (char ';')
case lookupEntity ent of
Just c -> return c
Nothing -> fail "entity not found"
-- | Parses an uppercase roman numeral and returns (UpperRoman, number).
upperRoman :: Parser [Char] st (ListNumberStyle, Int)
upperRoman = do
num <- romanNumeral True
return (UpperRoman, num)
-- | Parses a lowercase roman numeral and returns (LowerRoman, number).
lowerRoman :: Parser [Char] st (ListNumberStyle, Int)
lowerRoman = do
num <- romanNumeral False
return (LowerRoman, num)
-- | Parses a decimal numeral and returns (Decimal, number).
decimal :: Parser [Char] st (ListNumberStyle, Int)
decimal = do
num <- many1 digit
return (Decimal, read num)
-- | Parses a '@' and optional label and
-- returns (DefaultStyle, [next example number]). The next
-- example number is incremented in parser state, and the label
-- (if present) is added to the label table.
exampleNum :: Parser [Char] ParserState (ListNumberStyle, Int)
exampleNum = do
char '@'
lab <- many (alphaNum <|> satisfy (\c -> c == '_' || c == '-'))
st <- getState
let num = stateNextExample st
let newlabels = if null lab
then stateExamples st
else M.insert lab num $ stateExamples st
updateState $ \s -> s{ stateNextExample = num + 1
, stateExamples = newlabels }
return (Example, num)
-- | Parses a '#' returns (DefaultStyle, 1).
defaultNum :: Parser [Char] st (ListNumberStyle, Int)
defaultNum = do
char '#'
return (DefaultStyle, 1)
-- | Parses a lowercase letter and returns (LowerAlpha, number).
lowerAlpha :: Parser [Char] st (ListNumberStyle, Int)
lowerAlpha = do
ch <- oneOf ['a'..'z']
return (LowerAlpha, ord ch - ord 'a' + 1)
-- | Parses an uppercase letter and returns (UpperAlpha, number).
upperAlpha :: Parser [Char] st (ListNumberStyle, Int)
upperAlpha = do
ch <- oneOf ['A'..'Z']
return (UpperAlpha, ord ch - ord 'A' + 1)
-- | Parses a roman numeral i or I
romanOne :: Parser [Char] st (ListNumberStyle, Int)
romanOne = (char 'i' >> return (LowerRoman, 1)) <|>
(char 'I' >> return (UpperRoman, 1))
-- | Parses an ordered list marker and returns list attributes.
anyOrderedListMarker :: Parser [Char] ParserState ListAttributes
anyOrderedListMarker = choice $
[delimParser numParser | delimParser <- [inPeriod, inOneParen, inTwoParens],
numParser <- [decimal, exampleNum, defaultNum, romanOne,
lowerAlpha, lowerRoman, upperAlpha, upperRoman]]
-- | Parses a list number (num) followed by a period, returns list attributes.
inPeriod :: Parser [Char] st (ListNumberStyle, Int)
-> Parser [Char] st ListAttributes
inPeriod num = try $ do
(style, start) <- num
char '.'
let delim = if style == DefaultStyle
then DefaultDelim
else Period
return (start, style, delim)
-- | Parses a list number (num) followed by a paren, returns list attributes.
inOneParen :: Parser [Char] st (ListNumberStyle, Int)
-> Parser [Char] st ListAttributes
inOneParen num = try $ do
(style, start) <- num
char ')'
return (start, style, OneParen)
-- | Parses a list number (num) enclosed in parens, returns list attributes.
inTwoParens :: Parser [Char] st (ListNumberStyle, Int)
-> Parser [Char] st ListAttributes
inTwoParens num = try $ do
char '('
(style, start) <- num
char ')'
return (start, style, TwoParens)
-- | Parses an ordered list marker with a given style and delimiter,
-- returns number.
orderedListMarker :: ListNumberStyle
-> ListNumberDelim
-> Parser [Char] ParserState Int
orderedListMarker style delim = do
let num = defaultNum <|> -- # can continue any kind of list
case style of
DefaultStyle -> decimal
Example -> exampleNum
Decimal -> decimal
UpperRoman -> upperRoman
LowerRoman -> lowerRoman
UpperAlpha -> upperAlpha
LowerAlpha -> lowerAlpha
let context = case delim of
DefaultDelim -> inPeriod
Period -> inPeriod
OneParen -> inOneParen
TwoParens -> inTwoParens
(start, _, _) <- context num
return start
-- | Parses a character reference and returns a Str element.
charRef :: Parser [Char] st Inline
charRef = do
c <- characterReference
return $ Str [c]
-- | Parse a table using 'headerParser', 'rowParser',
-- 'lineParser', and 'footerParser'.
tableWith :: Parser [Char] ParserState ([[Block]], [Alignment], [Int])
-> ([Int] -> Parser [Char] ParserState [[Block]])
-> Parser [Char] ParserState sep
-> Parser [Char] ParserState end
-> Parser [Char] ParserState Block
tableWith headerParser rowParser lineParser footerParser = try $ do
(heads, aligns, indices) <- headerParser
lines' <- rowParser indices `sepEndBy1` lineParser
footerParser
numColumns <- getOption readerColumns
let widths = if (indices == [])
then replicate (length aligns) 0.0
else widthsFromIndices numColumns indices
return $ Table [] aligns widths heads lines'
-- Calculate relative widths of table columns, based on indices
widthsFromIndices :: Int -- Number of columns on terminal
-> [Int] -- Indices
-> [Double] -- Fractional relative sizes of columns
widthsFromIndices _ [] = []
widthsFromIndices numColumns' indices =
let numColumns = max numColumns' (if null indices then 0 else last indices)
lengths' = zipWith (-) indices (0:indices)
lengths = reverse $
case reverse lengths' of
[] -> []
[x] -> [x]
-- compensate for the fact that intercolumn
-- spaces are counted in widths of all columns
-- but the last...
(x:y:zs) -> if x < y && y - x <= 2
then y:y:zs
else x:y:zs
totLength = sum lengths
quotient = if totLength > numColumns
then fromIntegral totLength
else fromIntegral numColumns
fracs = map (\l -> (fromIntegral l) / quotient) lengths in
tail fracs
---
-- Parse a grid table: starts with row of '-' on top, then header
-- (which may be grid), then the rows,
-- which may be grid, separated by blank lines, and
-- ending with a footer (dashed line followed by blank line).
gridTableWith :: Parser [Char] ParserState [Block] -- ^ Block list parser
-> Bool -- ^ Headerless table
-> Parser [Char] ParserState Block
gridTableWith blocks headless =
tableWith (gridTableHeader headless blocks) (gridTableRow blocks)
(gridTableSep '-') gridTableFooter
gridTableSplitLine :: [Int] -> String -> [String]
gridTableSplitLine indices line = map removeFinalBar $ tail $
splitStringByIndices (init indices) $ trimr line
gridPart :: Char -> Parser [Char] st (Int, Int)
gridPart ch = do
dashes <- many1 (char ch)
char '+'
return (length dashes, length dashes + 1)
gridDashedLines :: Char -> Parser [Char] st [(Int,Int)]
gridDashedLines ch = try $ char '+' >> many1 (gridPart ch) >>~ blankline
removeFinalBar :: String -> String
removeFinalBar =
reverse . dropWhile (`elem` " \t") . dropWhile (=='|') . reverse
-- | Separator between rows of grid table.
gridTableSep :: Char -> Parser [Char] ParserState Char
gridTableSep ch = try $ gridDashedLines ch >> return '\n'
-- | Parse header for a grid table.
gridTableHeader :: Bool -- ^ Headerless table
-> Parser [Char] ParserState [Block]
-> Parser [Char] ParserState ([[Block]], [Alignment], [Int])
gridTableHeader headless blocks = try $ do
optional blanklines
dashes <- gridDashedLines '-'
rawContent <- if headless
then return $ repeat ""
else many1
(notFollowedBy (gridTableSep '=') >> char '|' >>
many1Till anyChar newline)
if headless
then return ()
else gridTableSep '=' >> return ()
let lines' = map snd dashes
let indices = scanl (+) 0 lines'
let aligns = replicate (length lines') AlignDefault
-- RST does not have a notion of alignments
let rawHeads = if headless
then replicate (length dashes) ""
else map (intercalate " ") $ transpose
$ map (gridTableSplitLine indices) rawContent
heads <- mapM (parseFromString blocks) $ map trim rawHeads
return (heads, aligns, indices)
gridTableRawLine :: [Int] -> Parser [Char] ParserState [String]
gridTableRawLine indices = do
char '|'
line <- many1Till anyChar newline
return (gridTableSplitLine indices line)
-- | Parse row of grid table.
gridTableRow :: Parser [Char] ParserState [Block]
-> [Int]
-> Parser [Char] ParserState [[Block]]
gridTableRow blocks indices = do
colLines <- many1 (gridTableRawLine indices)
let cols = map ((++ "\n") . unlines . removeOneLeadingSpace) $
transpose colLines
mapM (liftM compactifyCell . parseFromString blocks) cols
removeOneLeadingSpace :: [String] -> [String]
removeOneLeadingSpace xs =
if all startsWithSpace xs
then map (drop 1) xs
else xs
where startsWithSpace "" = True
startsWithSpace (y:_) = y == ' '
compactifyCell :: [Block] -> [Block]
compactifyCell bs = head $ compactify [bs]
-- | Parse footer for a grid table.
gridTableFooter :: Parser [Char] ParserState [Char]
gridTableFooter = blanklines
---
-- | Parse a string with a given parser and state.
readWith :: Parser [t] ParserState a -- ^ parser
-> ParserState -- ^ initial state
-> [t] -- ^ input
-> a
readWith parser state input =
case runParser parser state "source" input of
Left err' -> error $ "\nError:\n" ++ show err'
Right result -> result
-- | Parse a string with @parser@ (for testing).
testStringWith :: (Show a) => Parser [Char] ParserState a
-> String
-> IO ()
testStringWith parser str = UTF8.putStrLn $ show $
readWith parser defaultParserState str
-- | Parsing options.
data ParserState = ParserState
{ stateOptions :: ReaderOptions, -- ^ User options
stateParserContext :: ParserContext, -- ^ Inside list?
stateQuoteContext :: QuoteContext, -- ^ Inside quoted environment?
stateAllowLinks :: Bool, -- ^ Allow parsing of links
stateMaxNestingLevel :: Int, -- ^ Max # of nested Strong/Emph
stateLastStrPos :: Maybe SourcePos, -- ^ Position after last str parsed
stateKeys :: KeyTable, -- ^ List of reference keys (with fallbacks)
stateSubstitutions :: SubstTable, -- ^ List of substitution references
stateNotes :: NoteTable, -- ^ List of notes (raw bodies)
stateNotes' :: NoteTable', -- ^ List of notes (parsed bodies)
stateTitle :: [Inline], -- ^ Title of document
stateAuthors :: [[Inline]], -- ^ Authors of document
stateDate :: [Inline], -- ^ Date of document
stateHeaderTable :: [HeaderType], -- ^ Ordered list of header types used
stateHeaders :: [[Inline]], -- ^ List of headers (used for implicit ref links)
stateNextExample :: Int, -- ^ Number of next example
stateExamples :: M.Map String Int, -- ^ Map from example labels to numbers
stateHasChapters :: Bool, -- ^ True if \chapter encountered
stateMacros :: [Macro], -- ^ List of macros defined so far
stateRstDefaultRole :: String, -- ^ Current rST default interpreted text role
stateWarnings :: [String] -- ^ Warnings generated by the parser
}
instance Default ParserState where
def = defaultParserState
defaultParserState :: ParserState
defaultParserState =
ParserState { stateOptions = def,
stateParserContext = NullState,
stateQuoteContext = NoQuote,
stateAllowLinks = True,
stateMaxNestingLevel = 6,
stateLastStrPos = Nothing,
stateKeys = M.empty,
stateSubstitutions = M.empty,
stateNotes = [],
stateNotes' = [],
stateTitle = [],
stateAuthors = [],
stateDate = [],
stateHeaderTable = [],
stateHeaders = [],
stateNextExample = 1,
stateExamples = M.empty,
stateHasChapters = False,
stateMacros = [],
stateRstDefaultRole = "title-reference",
stateWarnings = []}
getOption :: (ReaderOptions -> a) -> Parser s ParserState a
getOption f = (f . stateOptions) `fmap` getState
-- | Succeed only if the extension is enabled.
guardEnabled :: Extension -> Parser s ParserState ()
guardEnabled ext = getOption readerExtensions >>= guard . Set.member ext
-- | Succeed only if the extension is disabled.
guardDisabled :: Extension -> Parser s ParserState ()
guardDisabled ext = getOption readerExtensions >>= guard . not . Set.member ext
data HeaderType
= SingleHeader Char -- ^ Single line of characters underneath
| DoubleHeader Char -- ^ Lines of characters above and below
deriving (Eq, Show)
data ParserContext
= ListItemState -- ^ Used when running parser on list item contents
| NullState -- ^ Default state
deriving (Eq, Show)
data QuoteContext
= InSingleQuote -- ^ Used when parsing inside single quotes
| InDoubleQuote -- ^ Used when parsing inside double quotes
| NoQuote -- ^ Used when not parsing inside quotes
deriving (Eq, Show)
type NoteTable = [(String, String)]
type NoteTable' = [(String, F Blocks)] -- used in markdown reader
newtype Key = Key String deriving (Show, Read, Eq, Ord)
toKey :: String -> Key
toKey = Key . map toLower . unwords . words
type KeyTable = M.Map Key Target
type SubstTable = M.Map Key Inlines
-- | Fail unless we're in "smart typography" mode.
failUnlessSmart :: Parser [tok] ParserState ()
failUnlessSmart = getOption readerSmart >>= guard
smartPunctuation :: Parser [Char] ParserState Inline
-> Parser [Char] ParserState Inline
smartPunctuation inlineParser = do
failUnlessSmart
choice [ quoted inlineParser, apostrophe, dash, ellipses ]
apostrophe :: Parser [Char] ParserState Inline
apostrophe = (char '\'' <|> char '\8217') >> return (Str "\x2019")
quoted :: Parser [Char] ParserState Inline
-> Parser [Char] ParserState Inline
quoted inlineParser = doubleQuoted inlineParser <|> singleQuoted inlineParser
withQuoteContext :: QuoteContext
-> Parser [tok] ParserState a
-> Parser [tok] ParserState a
withQuoteContext context parser = do
oldState <- getState
let oldQuoteContext = stateQuoteContext oldState
setState oldState { stateQuoteContext = context }
result <- parser
newState <- getState
setState newState { stateQuoteContext = oldQuoteContext }
return result
singleQuoted :: Parser [Char] ParserState Inline
-> Parser [Char] ParserState Inline
singleQuoted inlineParser = try $ do
singleQuoteStart
withQuoteContext InSingleQuote $ many1Till inlineParser singleQuoteEnd >>=
return . Quoted SingleQuote . normalizeSpaces
doubleQuoted :: Parser [Char] ParserState Inline
-> Parser [Char] ParserState Inline
doubleQuoted inlineParser = try $ do
doubleQuoteStart
withQuoteContext InDoubleQuote $ do
contents <- manyTill inlineParser doubleQuoteEnd
return . Quoted DoubleQuote . normalizeSpaces $ contents
failIfInQuoteContext :: QuoteContext -> Parser [tok] ParserState ()
failIfInQuoteContext context = do
st <- getState
if stateQuoteContext st == context
then fail "already inside quotes"
else return ()
charOrRef :: [Char] -> Parser [Char] st Char
charOrRef cs =
oneOf cs <|> try (do c <- characterReference
guard (c `elem` cs)
return c)
updateLastStrPos :: Parser [Char] ParserState ()
updateLastStrPos = getPosition >>= \p ->
updateState $ \s -> s{ stateLastStrPos = Just p }
singleQuoteStart :: Parser [Char] ParserState ()
singleQuoteStart = do
failIfInQuoteContext InSingleQuote
pos <- getPosition
st <- getState
-- single quote start can't be right after str
guard $ stateLastStrPos st /= Just pos
try $ do charOrRef "'\8216\145"
notFollowedBy (oneOf ")!],;:-? \t\n")
notFollowedBy (char '.') <|> lookAhead (string "..." >> return ())
notFollowedBy (try (oneOfStrings ["s","t","m","ve","ll","re"] >>
satisfy (not . isAlphaNum)))
-- possess/contraction
return ()
singleQuoteEnd :: Parser [Char] st ()
singleQuoteEnd = try $ do
charOrRef "'\8217\146"
notFollowedBy alphaNum
doubleQuoteStart :: Parser [Char] ParserState ()
doubleQuoteStart = do
failIfInQuoteContext InDoubleQuote
try $ do charOrRef "\"\8220\147"
notFollowedBy (satisfy (\c -> c == ' ' || c == '\t' || c == '\n'))
doubleQuoteEnd :: Parser [Char] st ()
doubleQuoteEnd = do
charOrRef "\"\8221\148"
return ()
ellipses :: Parser [Char] st Inline
ellipses = do
try (charOrRef "\8230\133") <|> try (string "..." >> return '…')
return (Str "\8230")
dash :: Parser [Char] ParserState Inline
dash = do
oldDashes <- getOption readerOldDashes
if oldDashes
then emDashOld <|> enDashOld
else Str `fmap` (hyphenDash <|> emDash <|> enDash)
-- Two hyphens = en-dash, three = em-dash
hyphenDash :: Parser [Char] st String
hyphenDash = do
try $ string "--"
option "\8211" (char '-' >> return "\8212")
emDash :: Parser [Char] st String
emDash = do
try (charOrRef "\8212\151")
return "\8212"
enDash :: Parser [Char] st String
enDash = do
try (charOrRef "\8212\151")
return "\8211"
enDashOld :: Parser [Char] st Inline
enDashOld = do
try (charOrRef "\8211\150") <|>
try (char '-' >> lookAhead (satisfy isDigit) >> return '')
return (Str "\8211")
emDashOld :: Parser [Char] st Inline
emDashOld = do
try (charOrRef "\8212\151") <|> (try $ string "--" >> optional (char '-') >> return '-')
return (Str "\8212")
-- This is used to prevent exponential blowups for things like:
-- a**a*a**a*a**a*a**a*a**a*a**a*a**
nested :: Parser s ParserState a
-> Parser s ParserState a
nested p = do
nestlevel <- stateMaxNestingLevel `fmap` getState
guard $ nestlevel > 0
updateState $ \st -> st{ stateMaxNestingLevel = stateMaxNestingLevel st - 1 }
res <- p
updateState $ \st -> st{ stateMaxNestingLevel = nestlevel }
return res
--
-- Macros
--
-- | Parse a \newcommand or \renewcommand macro definition.
macro :: Parser [Char] ParserState Block
macro = do
apply <- getOption readerApplyMacros
inp <- getInput
case parseMacroDefinitions inp of
([], _) -> mzero
(ms, rest) -> do def' <- count (length inp - length rest) anyChar
if apply
then do
updateState $ \st ->
st { stateMacros = ms ++ stateMacros st }
return Null
else return $ RawBlock "latex" def'
-- | Apply current macros to string.
applyMacros' :: String -> Parser [Char] ParserState String
applyMacros' target = do
apply <- getOption readerApplyMacros
if apply
then do macros <- liftM stateMacros getState
return $ applyMacros macros target
else return target