From 655363da5147b3b1483dc9ccd7c8b50f865815e2 Mon Sep 17 00:00:00 2001 From: fiddlosopher Date: Mon, 9 Jul 2007 03:39:25 +0000 Subject: Moved Text.ParserCombinators.Pandoc -> Text.Pandoc.ParserCombinators. This way, all the Pandoc modules are in one place. git-svn-id: https://pandoc.googlecode.com/svn/trunk@663 788f1e2b-df1e-0410-8736-df70ead52e1b --- src/Text/Pandoc/ParserCombinators.hs | 124 +++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 src/Text/Pandoc/ParserCombinators.hs (limited to 'src/Text/Pandoc/ParserCombinators.hs') diff --git a/src/Text/Pandoc/ParserCombinators.hs b/src/Text/Pandoc/ParserCombinators.hs new file mode 100644 index 000000000..7a129b6be --- /dev/null +++ b/src/Text/Pandoc/ParserCombinators.hs @@ -0,0 +1,124 @@ +{- +Copyright (C) 2006-7 John MacFarlane + +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.ParserCombinators + Copyright : Copyright (C) 2006-7 John MacFarlane + License : GNU GPL, version 2 or above + + Maintainer : John MacFarlane + Stability : alpha + Portability : portable + +Parser combinators used in Pandoc readers. +-} +module Text.Pandoc.ParserCombinators ( + anyLine, + many1Till, + notFollowedBy', + oneOfStrings, + spaceChar, + skipSpaces, + blankline, + blanklines, + enclosed, + stringAnyCase, + parseFromStr, + lineClump + ) where +import Text.ParserCombinators.Parsec +import Data.Char ( toUpper, toLower ) + +--- | Parse any line of text +anyLine :: GenParser Char st [Char] +anyLine = try (manyTill anyChar newline) <|> many1 anyChar + -- second alternative is for a line ending with eof + +-- | Parses a space or tab. +spaceChar :: CharParser st Char +spaceChar = oneOf " \t" + +-- | Skips zero or more spaces or tabs. +skipSpaces :: GenParser Char st () +skipSpaces = skipMany spaceChar + +-- | Skips zero or more spaces or tabs, then reads a newline. +blankline :: GenParser Char st Char +blankline = try (do + skipSpaces + newline) + +-- | Parses one or more blank lines and returns a string of newlines. +blanklines :: GenParser Char st [Char] +blanklines = try (many1 blankline) + +-- | Parses material enclosed between start and end parsers. +enclosed :: GenParser Char st t -- ^ start parser + -> GenParser Char st end -- ^ end parser + -> GenParser Char st a -- ^ content parser (to be used repeatedly) + -> GenParser Char st [a] +enclosed start end parser = try (do + start + notFollowedBy space + result <- many1Till parser end + return result) + +-- | Like @manyTill@, but reads at least one item. +many1Till :: GenParser tok st a + -> GenParser tok st end + -> GenParser tok st [a] +many1Till p end = try (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 => GenParser a st b -> GenParser a st () +notFollowedBy' parser = try (do { c <- try parser; unexpected (show c) } + <|> return ()) + +-- | Parses one of a list of strings (tried in order). +oneOfStrings :: [String] -> GenParser Char st String +oneOfStrings listOfStrings = choice $ map (try . string) listOfStrings + +-- | Parse string, case insensitive. +stringAnyCase :: [Char] -> CharParser st String +stringAnyCase [] = string "" +stringAnyCase (x:xs) = try (do + firstChar <- choice [ char (toUpper x), char (toLower x) ] + rest <- stringAnyCase xs + return (firstChar:rest)) + +-- | Parse contents of 'str' using 'parser' and return result. +parseFromStr :: GenParser tok st a -> [tok] -> GenParser tok st a +parseFromStr parser str = try $ do + oldInput <- getInput + setInput str + result <- parser + setInput oldInput + return result + +-- | Parse raw line block up to and including blank lines. +lineClump :: GenParser Char st String +lineClump = do + lines <- many1 (do{notFollowedBy blankline; anyLine}) + blanks <- blanklines <|> (do{eof; return "\n"}) + return ((unlines lines) ++ blanks) + -- cgit v1.2.3