From f7b705b44cfff881d12501eb8061ebdf20627632 Mon Sep 17 00:00:00 2001 From: fiddlosopher Date: Thu, 22 Nov 2007 17:14:21 +0000 Subject: Implemented implicit reference-style links to section headers in markdown. For example, if you have a header '# Supported architectures', you can link to it with '[Supported architectures]'. If there are multiple headers with this label, the link will point to the first of them. Implicit references are always overridden by explicitly specified references. Addresses Issue #20. + Moved isPunctuation, uniqueIdentifiers, and inlineListToIdentifier from Text.Pandoc.Writers.HTML to Text.Pandoc.Shared. + Added stHeaders to ParserState. This holds a list of header texts used in the document, and is used to construct implicit header references. + In Text.Pandoc.Readers.Markdown, added call to headerReference parser in initial parsing pass, constructing a list of section header labels. This is then passed to uniqueIdentifiers to produce identifiers, and a list of implicit references is constructed. This is added to the end of the explicitly specified references, so it will be overridden by explicitly specified references. All of this processing is skipped if --strict was specified. + Modified documentation in README. git-svn-id: https://pandoc.googlecode.com/svn/trunk@1086 788f1e2b-df1e-0410-8736-df70ead52e1b --- src/Text/Pandoc/Readers/Markdown.hs | 169 ++++++++++++++++++++---------------- 1 file changed, 94 insertions(+), 75 deletions(-) (limited to 'src/Text/Pandoc/Readers/Markdown.hs') diff --git a/src/Text/Pandoc/Readers/Markdown.hs b/src/Text/Pandoc/Readers/Markdown.hs index e50180a63..05a46c511 100644 --- a/src/Text/Pandoc/Readers/Markdown.hs +++ b/src/Text/Pandoc/Readers/Markdown.hs @@ -19,7 +19,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA {- | Module : Text.Pandoc.Readers.Markdown Copyright : Copyright (C) 2006-7 John MacFarlane - License : GNU GPL, version 2 or above + License : GNU GPL, version 2 or above Maintainer : John MacFarlane Stability : alpha @@ -27,8 +27,8 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Conversion of markdown-formatted plain text to 'Pandoc' document. -} -module Text.Pandoc.Readers.Markdown ( - readMarkdown +module Text.Pandoc.Readers.Markdown ( + readMarkdown ) where import Data.List ( transpose, isPrefixOf, isSuffixOf, lookup, sortBy ) @@ -36,9 +36,9 @@ import Data.Ord ( comparing ) import Data.Char ( isAlphaNum ) import Network.URI ( isURI ) import Text.Pandoc.Definition -import Text.Pandoc.Shared +import Text.Pandoc.Shared import Text.Pandoc.Readers.LaTeX ( rawLaTeXInline, rawLaTeXEnvironment ) -import Text.Pandoc.Readers.HTML ( rawHtmlBlock, anyHtmlBlockTag, +import Text.Pandoc.Readers.HTML ( rawHtmlBlock, anyHtmlBlockTag, anyHtmlInlineTag, anyHtmlTag, anyHtmlEndTag, htmlEndTag, extractTagType, htmlBlockElement ) @@ -68,14 +68,14 @@ specialChars = "\\[]*_~`<>$!^-.&'\"\8216\8217\8220\8221" indentSpaces = try $ do state <- getState let tabStop = stateTabStop state - try (count tabStop (char ' ')) <|> + try (count tabStop (char ' ')) <|> (many (char ' ') >> string "\t") "indentation" nonindentSpaces = do state <- getState let tabStop = stateTabStop state sps <- many (char ' ') - if length sps < tabStop + if length sps < tabStop then return sps else unexpected "indented line" @@ -90,8 +90,8 @@ failUnlessSmart = do if stateSmart state then return () else fail "Smart typography feature" -- | Parse an inline Str element with a given content. -inlineString str = try $ do - (Str res) <- inline +inlineString str = try $ do + (Str res) <- inline if res == str then return res else fail $ "unexpected Str content" -- | Parse a sequence of inline elements between a string @@ -102,9 +102,9 @@ inlinesInBalanced opener closer = try $ do string opener result <- manyTill ( (do lookAhead (inlineString opener) -- because it might be a link... - bal <- inlinesInBalanced opener closer + bal <- inlinesInBalanced opener closer return $ [Str opener] ++ bal ++ [Str closer]) - <|> (count 1 inline)) + <|> (count 1 inline)) (try (string closer)) return $ concat result @@ -114,7 +114,7 @@ inlinesInBalanced opener closer = try $ do titleLine = try $ char '%' >> skipSpaces >> manyTill inline newline -authorsLine = try $ do +authorsLine = try $ do char '%' skipSpaces authors <- sepEndBy (many1 (noneOf ",;\n")) (oneOf ",;") @@ -142,15 +142,24 @@ parseMarkdown = do startPos <- getPosition -- go through once just to get list of reference keys -- docMinusKeys is the raw document with blanks where the keys were... - docMinusKeys <- manyTill (referenceKey <|> lineClump) eof >>= - return . concat + docMinusKeys <- manyTill (referenceKey <|> headerReference <|> + lineClump) eof >>= return . concat setInput docMinusKeys setPosition startPos st <- getState + -- get headers and construct implicit references unless strict + if stateStrict st + then return () + else do let oldkeys = stateKeys st + let headers = reverse $ stateHeaders st + let idents = uniqueIdentifiers headers + let implicitRefs = zipWith (\hd ident -> (hd, ("#" ++ ident, ""))) + headers idents + updateState $ \st -> st { stateKeys = oldkeys ++ implicitRefs } -- go through again for notes unless strict... if stateStrict st then return () - else do docMinusNotes <- manyTill (noteBlock <|> lineClump) eof >>= + else do docMinusNotes <- manyTill (noteBlock <|> lineClump) eof >>= return . concat st <- getState let reversedNotes = stateNotes st @@ -159,10 +168,10 @@ parseMarkdown = do setPosition startPos -- now parse it for real... (title, author, date) <- option ([],[],"") titleBlock - blocks <- parseBlocks + blocks <- parseBlocks return $ Pandoc (Meta title author date) $ filter (/= Null) blocks --- +-- -- initial pass for references and notes -- @@ -185,7 +194,17 @@ referenceKey = try $ do -- return blanks so line count isn't affected return $ replicate (sourceLine endPos - sourceLine startPos) '\n' -referenceTitle = try $ do +headerReference = try $ do + failIfStrict + startPos <- getPosition + (Header level text) <- lookAhead $ atxHeader <|> setextHeader + st <- getState + let headers = stateHeaders st + updateState $ \st -> st { stateHeaders = text:headers } + endPos <- getPosition + lineClump -- return the raw header, because we need to parse it later + +referenceTitle = try $ do (many1 spaceChar >> option '\n' newline) <|> newline skipSpaces tit <- (charsInBalanced '(' ')' >>= return . unwords . words) @@ -200,7 +219,7 @@ rawLine = do notFollowedBy blankline notFollowedBy' noteMarker contents <- many1 nonEndline - end <- option "" (newline >> optional indentSpaces >> return "\n") + end <- option "" (newline >> optional indentSpaces >> return "\n") return $ contents ++ end rawLines = many1 rawLine >>= return . concat @@ -229,7 +248,7 @@ noteBlock = try $ do parseBlocks = manyTill block eof -block = choice [ header +block = choice [ header , table , codeBlock , hrule @@ -260,7 +279,7 @@ setextHeader = try $ do -- first, see if this block has any chance of being a setextHeader: lookAhead (anyLine >> oneOf setextHChars) text <- many1Till inline newline >>= return . normalizeSpaces - level <- choice $ zipWith + level <- choice $ zipWith (\ch lev -> try (many1 $ char ch) >> blanklines >> return lev) setextHChars [1..(length setextHChars)] return $ Header level text @@ -285,7 +304,7 @@ hrule = try $ do indentedLine = indentSpaces >> manyTill anyChar newline >>= return . (++ "\n") codeBlock = do - contents <- many1 (indentedLine <|> + contents <- many1 (indentedLine <|> try (do b <- blanklines l <- indentedLine return $ b ++ l)) @@ -300,7 +319,7 @@ emacsBoxQuote = try $ do failIfStrict string ",----" manyTill anyChar newline - raw <- manyTill + raw <- manyTill (try (char '|' >> optional (char ' ') >> manyTill anyChar newline)) (try (string "`----")) blanklines @@ -310,7 +329,7 @@ emailBlockQuoteStart = try $ nonindentSpaces >> char '>' >>~ optional (char ' ') emailBlockQuote = try $ do emailBlockQuoteStart - raw <- sepBy (many (nonEndline <|> + raw <- sepBy (many (nonEndline <|> (try (endline >> notFollowedBy emailBlockQuoteStart >> return '\n')))) (try (newline >> emailBlockQuoteStart)) @@ -318,12 +337,12 @@ emailBlockQuote = try $ do optional blanklines return raw -blockQuote = do +blockQuote = do raw <- emailBlockQuote <|> emacsBoxQuote -- parse the extracted block, which may contain various block elements: contents <- parseFromString parseBlocks $ (joinWithSep "\n" raw) ++ "\n\n" return $ BlockQuote contents - + -- -- list blocks -- @@ -358,7 +377,7 @@ orderedListStart style delim = try $ do then do many1 digit char '.' return 1 - else orderedListMarker style delim + else orderedListMarker style delim if delim == Period && (style == UpperAlpha || (style == UpperRoman && num `elem` [1, 5, 10, 50, 100, 500, 1000])) then char '\t' <|> (spaceChar >> spaceChar) @@ -382,7 +401,7 @@ rawListItem start = try $ do blanks <- many blankline return $ concat result ++ blanks --- continuation of a list item - indented and separated by blankline +-- continuation of a list item - indented and separated by blankline -- or (in compact lists) endline. -- note: nested lists are parsed as continuations listContinuation start = try $ do @@ -398,7 +417,7 @@ listContinuationLine start = try $ do result <- manyTill anyChar newline return $ result ++ "\n" -listItem start = try $ do +listItem start = try $ do first <- rawListItem start continuations <- many (listContinuation start) -- parsing with ListItemState forces markers at beginning of lines to @@ -418,7 +437,7 @@ orderedList = try $ do items <- many1 (listItem (orderedListStart style delim)) return $ OrderedList (start, style, delim) $ compactify items -bulletList = many1 (listItem bulletListStart) >>= +bulletList = many1 (listItem bulletListStart) >>= return . BulletList . compactify -- definition lists @@ -459,7 +478,7 @@ definitionList = do -- paragraph block -- -para = try $ do +para = try $ do result <- many1 inline newline blanklines <|> do st <- getState @@ -468,9 +487,9 @@ para = try $ do else lookAhead emacsBoxQuote >> return "" return $ Para $ normalizeSpaces result -plain = many1 inline >>= return . Plain . normalizeSpaces +plain = many1 inline >>= return . Plain . normalizeSpaces --- +-- -- raw html -- @@ -487,25 +506,25 @@ htmlBlock = do else rawHtmlBlocks -- True if tag is self-closing -isSelfClosing tag = +isSelfClosing tag = isSuffixOf "/>" $ filter (not . (`elem` " \n\t")) tag strictHtmlBlock = try $ do - tag <- anyHtmlBlockTag + tag <- anyHtmlBlockTag let tag' = extractTagType tag - if isSelfClosing tag || tag' == "hr" + if isSelfClosing tag || tag' == "hr" then return tag - else do contents <- many (notFollowedBy' (htmlEndTag tag') >> + else do contents <- many (notFollowedBy' (htmlEndTag tag') >> (htmlElement <|> (count 1 anyChar))) end <- htmlEndTag tag' return $ tag ++ concat contents ++ end rawHtmlBlocks = do - htmlBlocks <- many1 rawHtmlBlock + htmlBlocks <- many1 rawHtmlBlock let combined = concatMap (\(RawHtml str) -> str) htmlBlocks let combined' = if not (null combined) && last combined == '\n' - then init combined -- strip extra newline - else combined + then init combined -- strip extra newline + else combined return $ RawHtml combined' -- @@ -516,7 +535,7 @@ rawLaTeXEnvironment' = failIfStrict >> rawLaTeXEnvironment -- -- Tables --- +-- -- Parse a dashed line with optional trailing spaces; return its length -- and the length including trailing space. @@ -525,7 +544,7 @@ dashedLine ch = do sp <- many spaceChar return $ (length dashes, length $ dashes ++ sp) --- Parse a table header with dashed lines of '-' preceded by +-- Parse a table header with dashed lines of '-' preceded by -- one line of text. simpleTableHeader = try $ do rawContent <- anyLine @@ -548,7 +567,7 @@ tableSep = try $ nonindentSpaces >> many1 (dashedLine '-') >> string "\n" rawTableLine indices = do notFollowedBy' (blanklines <|> tableFooter) line <- many1Till anyChar newline - return $ map removeLeadingTrailingSpace $ tail $ + return $ map removeLeadingTrailingSpace $ tail $ splitByIndices (init indices) line -- Parse a table line and return a list of lists of blocks (columns). @@ -565,8 +584,8 @@ multilineRow indices = do widthsFromIndices :: Int -- Number of columns on terminal -> [Int] -- Indices -> [Float] -- Fractional relative sizes of columns -widthsFromIndices _ [] = [] -widthsFromIndices numColumns indices = +widthsFromIndices _ [] = [] +widthsFromIndices numColumns indices = let lengths = zipWith (-) indices (0:indices) totLength = sum lengths quotient = if totLength > numColumns @@ -605,14 +624,14 @@ simpleTable = tableWith simpleTableHeader tableLine blanklines multilineTable = tableWith multilineTableHeader multilineRow tableFooter multilineTableHeader = try $ do - tableSep + tableSep rawContent <- many1 (notFollowedBy' tableSep >> many1Till anyChar newline) initSp <- nonindentSpaces dashes <- many1 (dashedLine '-') newline let (lengths, lines) = unzip dashes let indices = scanl (+) (length initSp) lines - let rawHeadsList = transpose $ map + let rawHeadsList = transpose $ map (\ln -> tail $ splitByIndices (init indices) ln) rawContent let rawHeads = map (joinWithSep " ") rawHeadsList @@ -625,7 +644,7 @@ multilineTableHeader = try $ do alignType :: [String] -> Int -> Alignment alignType [] len = AlignDefault alignType strLst len = - let str = head $ sortBy (comparing length) $ + let str = head $ sortBy (comparing length) $ map removeTrailingSpace strLst leftSpace = if null str then False else (str !! 0) `elem` " \t" rightSpace = length str < len || (str !! (len - 1)) `elem` " \t" @@ -637,7 +656,7 @@ alignType strLst len = table = failIfStrict >> (simpleTable <|> multilineTable) "table" --- +-- -- inline -- @@ -667,7 +686,7 @@ inline = choice [ str escapedChar = do char '\\' state <- getState - result <- option '\\' $ if stateStrict state + result <- option '\\' $ if stateStrict state then oneOf "\\`*_{}[]()>#+-.!~" else satisfy (not . isAlphaNum) return $ Str [result] @@ -681,17 +700,17 @@ ltSign = do specialCharsMinusLt = filter (/= '<') specialChars -symbol = do +symbol = do result <- oneOf specialCharsMinusLt return $ Str [result] -- parses inline code, between n `s and n `s -code = try $ do +code = try $ do starts <- many1 (char '`') skipSpaces result <- many1Till (many1 (noneOf "`\n") <|> many1 (char '`') <|> - (char '\n' >> return " ")) - (try (skipSpaces >> count (length starts) (char '`') >> + (char '\n' >> return " ")) + (try (skipSpaces >> count (length starts) (char '`') >> notFollowedBy (char '`'))) return $ Code $ removeLeadingTrailingSpace $ concat result @@ -707,30 +726,30 @@ math = try $ do return $ TeX ("$" ++ (joinWithSep " " words) ++ "$") emph = ((enclosed (char '*') (char '*') inline) <|> - (enclosed (char '_') (char '_' >> notFollowedBy alphaNum) inline)) >>= + (enclosed (char '_') (char '_' >> notFollowedBy alphaNum) inline)) >>= return . Emph . normalizeSpaces -strong = ((enclosed (string "**") (try $ string "**") inline) <|> +strong = ((enclosed (string "**") (try $ string "**") inline) <|> (enclosed (string "__") (try $ string "__") inline)) >>= return . Strong . normalizeSpaces strikeout = failIfStrict >> enclosed (string "~~") (try $ string "~~") inline >>= return . Strikeout . normalizeSpaces -superscript = failIfStrict >> enclosed (char '^') (char '^') +superscript = failIfStrict >> enclosed (char '^') (char '^') (notFollowedBy' whitespace >> inline) >>= -- may not contain Space return . Superscript subscript = failIfStrict >> enclosed (char '~') (char '~') (notFollowedBy' whitespace >> inline) >>= -- may not contain Space - return . Subscript + return . Subscript -smartPunctuation = failUnlessSmart >> +smartPunctuation = failUnlessSmart >> choice [ quoted, apostrophe, dash, ellipses ] apostrophe = (char '\'' <|> char '\8217') >> return Apostrophe -quoted = doubleQuoted <|> singleQuoted +quoted = doubleQuoted <|> singleQuoted withQuoteContext context parser = do oldState <- getState @@ -746,7 +765,7 @@ singleQuoted = try $ do withQuoteContext InSingleQuote $ many1Till inline singleQuoteEnd >>= return . Quoted SingleQuote . normalizeSpaces -doubleQuoted = try $ do +doubleQuoted = try $ do doubleQuoteStart withQuoteContext InDoubleQuote $ many1Till inline doubleQuoteEnd >>= return . Quoted DoubleQuote . normalizeSpaces @@ -757,13 +776,13 @@ failIfInQuoteContext context = do then fail "already inside quotes" else return () -singleQuoteStart = do +singleQuoteStart = do failIfInQuoteContext InSingleQuote - char '\8216' <|> - (try $ do char '\'' + char '\8216' <|> + (try $ do char '\'' notFollowedBy (oneOf ")!],.;:-? \t\n") notFollowedBy (try (oneOfStrings ["s","t","m","ve","ll","re"] >> - satisfy (not . isAlphaNum))) + satisfy (not . isAlphaNum))) -- possess/contraction return '\'') @@ -807,13 +826,13 @@ endline = try $ do newline notFollowedBy blankline st <- getState - if stateStrict st + if stateStrict st then do notFollowedBy emailBlockQuoteStart notFollowedBy (char '#') -- atx header - else return () + else return () -- parse potential list-starts differently if in a list: if stateParserContext st == ListItemState - then notFollowedBy' (bulletListStart <|> + then notFollowedBy' (bulletListStart <|> (anyOrderedListStart >> return ())) else return () return Space @@ -827,7 +846,7 @@ reference = notFollowedBy' (string "[^") >> -- footnote reference inlinesInBalanced "[" "]" >>= (return . normalizeSpaces) -- source for a link, with optional title -source = try $ do +source = try $ do char '(' optional (char '<') src <- many (noneOf ")> \t\n") @@ -837,7 +856,7 @@ source = try $ do char ')' return (removeTrailingSpace src, tit) -linkTitle = try $ do +linkTitle = try $ do (many1 spaceChar >> option '\n' newline) <|> newline skipSpaces delim <- char '\'' <|> char '"' @@ -852,13 +871,13 @@ link = try $ do -- a link like [this][ref] or [this][] or [this] referenceLink label = do - ref <- option [] (try (optional (char ' ') >> + ref <- option [] (try (optional (char ' ') >> optional (newline >> skipSpaces) >> reference)) let ref' = if null ref then label else ref state <- getState case lookupKeySrc (stateKeys state) ref' of - Nothing -> fail "no corresponding key" - Just target -> return target + Nothing -> fail "no corresponding key" + Just target -> return target emailAddress = try $ do name <- many1 (alphaNum <|> char '+') @@ -879,7 +898,7 @@ autoLink = try $ do char '>' let src' = if "mailto:" `isPrefixOf` src then drop 7 src - else src + else src st <- getState return $ if stateStrict st then Link [Str src'] (src, "") @@ -910,7 +929,7 @@ rawLaTeXInline' = failIfStrict >> rawLaTeXInline rawHtmlInline' = do st <- getState result <- choice $ if stateStrict st - then [htmlBlockElement, anyHtmlTag, anyHtmlEndTag] + then [htmlBlockElement, anyHtmlTag, anyHtmlEndTag] else [htmlBlockElement, anyHtmlInlineTag] return $ HtmlInline result -- cgit v1.2.3