pandoc-3.2: src/Text/Pandoc/Writers/Markdown.hs
{-# LANGUAGE MultiWayIf #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TupleSections #-}
{-# LANGUAGE BangPatterns #-}
{- |
Module : Text.Pandoc.Writers.Markdown
Copyright : Copyright (C) 2006-2024 John MacFarlane
License : GNU GPL, version 2 or above
Maintainer : John MacFarlane <jgm@berkeley.edu>
Stability : alpha
Portability : portable
Conversion of 'Pandoc' documents to markdown-formatted plain text.
Markdown: <https://daringfireball.net/projects/markdown/>
-}
module Text.Pandoc.Writers.Markdown (
writeMarkdown,
writeCommonMark,
writeMarkua,
writePlain) where
import Control.Monad (foldM, zipWithM, MonadPlus(..), when)
import Control.Monad.Reader ( asks, MonadReader(local) )
import Control.Monad.State.Strict ( gets, modify )
import Data.Default
import Data.List (intersperse, sortOn, union)
import Data.List.NonEmpty (nonEmpty, NonEmpty(..))
import qualified Data.Map as M
import Data.Maybe (fromMaybe, mapMaybe, isNothing)
import qualified Data.Set as Set
import Data.Text (Text)
import Data.Char (isSpace)
import qualified Data.Text as T
import Text.HTML.TagSoup (Tag (..), isTagText, parseTags)
import Text.Pandoc.Class.PandocMonad (PandocMonad, report)
import Text.Pandoc.Definition
import Text.Pandoc.Logging
import Text.Pandoc.Options
import Text.Pandoc.Parsing hiding (blankline, blanklines, char, space)
import Text.DocLayout
import Text.Pandoc.Shared
import Text.Pandoc.Writers.Shared
import Text.Pandoc.Templates (renderTemplate)
import Text.DocTemplates (Val(..), Context(..), FromContext(..))
import Text.Pandoc.Walk
import Text.Pandoc.Writers.HTML (writeHtml5String)
import Text.Pandoc.Writers.Markdown.Inline (inlineListToMarkdown,
linkAttributes,
attrsToMarkdown,
attrsToMarkua)
import Text.Pandoc.Writers.Markdown.Table (pipeTable, pandocTable)
import Text.Pandoc.Writers.Markdown.Types (MarkdownVariant(..),
WriterState(..),
WriterEnv(..),
Ref, Refs, MD, evalMD)
-- | Convert Pandoc to Markdown.
writeMarkdown :: PandocMonad m => WriterOptions -> Pandoc -> m Text
writeMarkdown opts document =
evalMD (pandocToMarkdown opts{
writerWrapText = if isEnabled Ext_hard_line_breaks opts
then WrapNone
else writerWrapText opts }
document) def def
-- | Convert Pandoc to plain text (like markdown, but without links,
-- pictures, or inline formatting).
writePlain :: PandocMonad m => WriterOptions -> Pandoc -> m Text
writePlain opts document =
evalMD (pandocToMarkdown opts document) def{ envVariant = PlainText } def
-- | Convert Pandoc to Commonmark.
writeCommonMark :: PandocMonad m => WriterOptions -> Pandoc -> m Text
writeCommonMark opts document =
evalMD (pandocToMarkdown opts' document) def{ envVariant = Commonmark } def
where
opts' = opts{ writerExtensions =
-- These extensions can't be enabled or disabled
-- for commonmark because they're part of the core;
-- we set them here so that escapeText will behave
-- properly.
enableExtension Ext_all_symbols_escapable $
enableExtension Ext_intraword_underscores $
writerExtensions opts ,
writerWrapText =
if isEnabled Ext_hard_line_breaks opts
then WrapNone
else writerWrapText opts }
-- | Convert Pandoc to Markua.
writeMarkua :: PandocMonad m => WriterOptions -> Pandoc -> m Text
writeMarkua opts document =
evalMD (pandocToMarkdown opts' document) def{ envVariant = Markua } def
where
opts' = opts{ writerExtensions =
enableExtension Ext_hard_line_breaks $
enableExtension Ext_pipe_tables $
-- required for fancy list enumerators
enableExtension Ext_fancy_lists $
enableExtension Ext_startnum $
enableExtension Ext_strikeout $
enableExtension Ext_subscript $
enableExtension Ext_superscript $
enableExtension Ext_definition_lists $
enableExtension Ext_smart $
enableExtension Ext_footnotes
mempty ,
writerWrapText =
if isEnabled Ext_hard_line_breaks opts
then WrapNone
else writerWrapText opts }
pandocTitleBlock :: Doc Text -> [Doc Text] -> Doc Text -> Doc Text
pandocTitleBlock tit auths dat =
hang 2 (text "% ") tit <> cr <>
hang 2 (text "% ") (vcat $ map nowrap auths) <> cr <>
hang 2 (text "% ") dat <> cr
mmdTitleBlock :: Context Text -> Doc Text
mmdTitleBlock (Context hashmap) =
vcat $ map go $ sortOn (T.toCaseFold . fst) $ M.toList hashmap
where go (k,v) =
case (text (T.unpack k), v) of
(k', ListVal xs)
| null xs -> empty
| otherwise -> k' <> ":" <> space <>
hcat (intersperse "; " $
mapMaybe fromVal xs)
(k', SimpleVal x)
| isEmpty x -> empty
| otherwise -> k' <> ":" <> space <>
nest 2 (removeBlankLines (chomp x))
_ -> empty
removeBlankLines BlankLines{} = cr <> text "." <> cr
removeBlankLines (Concat x y) = removeBlankLines x <>
removeBlankLines y
removeBlankLines x = x
plainTitleBlock :: Doc Text -> [Doc Text] -> Doc Text -> Doc Text
plainTitleBlock tit auths dat =
tit <> cr <>
hcat (intersperse (text "; ") auths) <> cr <>
dat <> cr
yamlMetadataBlock :: Context Text -> Doc Text
yamlMetadataBlock v = "---" $$ contextToYaml v $$ "---"
contextToYaml :: Context Text -> Doc Text
contextToYaml (Context o) =
vcat $ map keyvalToYaml $ sortOn (T.toCaseFold . fst) $ M.toList o
where
keyvalToYaml (k,v) =
case (text (T.unpack k), v) of
(k', ListVal vs)
| null vs -> empty
| otherwise -> (k' <> ":") $$ valToYaml v
(k', MapVal (Context m))
| M.null m -> k' <> ": {}"
| otherwise -> (k' <> ":") $$ nest 2 (valToYaml v)
(_, SimpleVal x)
| isEmpty x -> empty
(_, NullVal) -> empty
(k', _) -> k' <> ":" <+> hang 2 "" (valToYaml v)
valToYaml :: Val Text -> Doc Text
valToYaml (ListVal xs) =
vcat $ map (\v -> hang 2 "- " (valToYaml v)) xs
valToYaml (MapVal c) = contextToYaml c
valToYaml (BoolVal True) = "true"
valToYaml (BoolVal False) = "false"
valToYaml (SimpleVal x)
| isEmpty x = empty
| otherwise =
if hasNewlines x
then hang 0 ("|" <> cr) x
else case x of
Text _ t | isSpecialString t ->
"\"" <> fmap escapeInDoubleQuotes x <> "\""
_ | isNothing (foldM needsDoubleQuotes True x) ->
"\"" <> fmap escapeInDoubleQuotes x <> "\""
| otherwise -> x
where
isSpecialString t = Set.member t specialStrings
specialStrings = Set.fromList
["y", "Y", "yes", "Yes", "YES", "n", "N",
"no", "No", "NO", "true", "True", "TRUE",
"false", "False", "FALSE", "on", "On", "ON",
"off", "Off", "OFF", "null", "Null",
"NULL", "~", "*"]
needsDoubleQuotes isFirst t
= if T.any isBadAnywhere t ||
(isFirst && T.any isYamlPunct (T.take 1 t))
then Nothing
else Just False
isBadAnywhere '#' = True
isBadAnywhere ':' = True
isBadAnywhere _ = False
hasNewlines NewLine = True
hasNewlines BlankLines{} = True
hasNewlines CarriageReturn = True
hasNewlines (Concat w z) = hasNewlines w || hasNewlines z
hasNewlines _ = False
isYamlPunct = (`elem` ['-','?',':',',','[',']','{','}',
'#','&','*','!','|','>','\'','"', '%','@','`'])
escapeInDoubleQuotes = T.replace "\"" "\\\"" . T.replace "\\" "\\\\"
valToYaml _ = empty
-- | Return markdown representation of document.
pandocToMarkdown :: PandocMonad m => WriterOptions -> Pandoc -> MD m Text
pandocToMarkdown opts (Pandoc meta blocks) = do
let colwidth = if writerWrapText opts == WrapAuto
then Just $ writerColumns opts
else Nothing
variant <- asks envVariant
metadata <- metaToContext'
(blockListToMarkdown opts)
(inlineListToMarkdown opts)
meta
let title' = fromMaybe empty $ getField "title" metadata
let authors' = fromMaybe [] $ getField "author" metadata
let date' = fromMaybe empty $ getField "date" metadata
let titleblock = case writerTemplate opts of
Just _ | variant == PlainText ->
plainTitleBlock title' authors' date'
| isEnabled Ext_yaml_metadata_block opts ->
yamlMetadataBlock metadata
| isEnabled Ext_pandoc_title_block opts ->
pandocTitleBlock title' authors' date'
| isEnabled Ext_mmd_title_block opts ->
mmdTitleBlock metadata
| otherwise -> empty
Nothing -> empty
let modifyTOC =
if isEnabled Ext_link_attributes opts || isEnabled Ext_attributes opts
then id
else walk $ \inln -> case inln of
Link _attr contents tgt -> Link nullAttr contents tgt
_ -> inln
toc <- if writerTableOfContents opts
then blockToMarkdown opts . modifyTOC $ toTableOfContents opts blocks
else return mempty
-- Strip off final 'references' header if markdown citations enabled
let blocks' = if isEnabled Ext_citations opts
then case reverse blocks of
(Div ("refs",_,_) _):xs -> reverse xs
_ -> blocks
else blocks
body <- blockListToMarkdown opts blocks'
notesAndRefs' <- notesAndRefs opts
let main = body <> notesAndRefs'
let context = -- for backwards compatibility we populate toc
-- with the contents of the toc, rather than a
-- boolean:
defField "toc" toc
$ defField "table-of-contents" toc
$ defField "body" main
$ (if isNullMeta meta
then id
else defField "titleblock" titleblock)
$ addVariablesToContext opts metadata
return $ render colwidth $
case writerTemplate opts of
Nothing -> main
Just tpl -> renderTemplate tpl context
-- | Return markdown representation of reference key table.
refsToMarkdown :: PandocMonad m => WriterOptions -> Refs -> MD m (Doc Text)
refsToMarkdown opts refs = vcat <$> mapM (keyToMarkdown opts) refs
-- | Return markdown representation of a reference key.
keyToMarkdown :: PandocMonad m
=> WriterOptions
-> Ref
-> MD m (Doc Text)
keyToMarkdown opts (label', (src, tit), attr) = do
let tit' = if T.null tit
then empty
else space <> "\"" <> literal tit <> "\""
return $ nest 2 $ hang 2
("[" <> literal label' <> "]:" <> space) (literal src <> tit')
<+> linkAttributes opts attr
-- | Return markdown representation of notes.
notesToMarkdown :: PandocMonad m => WriterOptions -> [[Block]] -> MD m (Doc Text)
notesToMarkdown opts notes = do
n <- gets stNoteNum
notes' <- zipWithM (noteToMarkdown opts) [n..] notes
modify $ \st -> st { stNoteNum = stNoteNum st + length notes }
return $ vsep notes'
-- | Return markdown representation of a note.
noteToMarkdown :: PandocMonad m => WriterOptions -> Int -> [Block] -> MD m (Doc Text)
noteToMarkdown opts num blocks = do
contents <- blockListToMarkdown opts blocks
let num' = literal $ writerIdentifierPrefix opts <> tshow num
let marker = if isEnabled Ext_footnotes opts
then literal "[^" <> num' <> literal "]:"
else literal "[" <> num' <> literal "]"
let markerSize = 4 + offset num'
let hspacer = case writerTabStop opts - markerSize of
n | n > 0 -> literal $ T.replicate n " "
_ -> literal " "
let spacer = case blocks of
Para{}:_ -> hspacer
Plain{}:_ -> hspacer
_ -> cr
return $ if isEnabled Ext_footnotes opts
then hang (writerTabStop opts) (marker <> spacer) contents
else marker <> spacer <> contents
-- | (Code) blocks with a single class and no attributes can just use it
-- standalone, no need to bother with curly braces.
classOrAttrsToMarkdown :: WriterOptions -> Attr -> Doc Text
classOrAttrsToMarkdown _ ("",[cls],[]) = literal cls
classOrAttrsToMarkdown opts attrs = attrsToMarkdown opts attrs
-- | Ordered list start parser for use in Para below.
olMarker :: Parsec Text ParserState ()
olMarker = do (start, style', delim) <- anyOrderedListMarker
if delim == Period &&
(style' == UpperAlpha || (style' == UpperRoman &&
start `elem` [1, 5, 10, 50, 100, 500, 1000]))
then mzero -- it needs 2 spaces anyway
else eof
-- | True if string begins with an ordered list marker
beginsWithOrderedListMarker :: Text -> Bool
beginsWithOrderedListMarker str =
case runParser olMarker defaultParserState "para start" (T.take 10 str) of
Left _ -> False
Right _ -> True
notesAndRefs :: PandocMonad m => WriterOptions -> MD m (Doc Text)
notesAndRefs opts = do
notes' <- gets stNotes >>= notesToMarkdown opts . reverse
modify $ \s -> s { stNotes = [] }
refs' <- gets stRefs >>= refsToMarkdown opts . reverse
modify $ \s -> s { stPrevRefs = stPrevRefs s ++ stRefs s
, stRefs = []}
let endSpacing =
if | writerReferenceLocation opts == EndOfDocument -> empty
| isEmpty notes' && isEmpty refs' -> empty
| otherwise -> blankline
return $
(if isEmpty notes' then empty else blankline <> notes') <>
(if isEmpty refs' then empty else blankline <> refs') <>
endSpacing
-- | Convert Pandoc block element to markdown.
blockToMarkdown :: PandocMonad m
=> WriterOptions -- ^ Options
-> Block -- ^ Block element
-> MD m (Doc Text)
blockToMarkdown opts blk =
local (\env -> env {envBlockLevel = envBlockLevel env + 1}) $
do doc <- blockToMarkdown' opts blk
blkLevel <- asks envBlockLevel
if writerReferenceLocation opts == EndOfBlock && blkLevel == 1
then notesAndRefs opts >>= (\d -> return $ doc <> d)
else return doc
blockToMarkdown' :: PandocMonad m
=> WriterOptions -- ^ Options
-> Block -- ^ Block element
-> MD m (Doc Text)
blockToMarkdown' opts (Div attrs@(_,classes,_) bs)
| isEnabled Ext_alerts opts
, (cls:_) <- classes
, cls `elem` ["note", "tip", "warning", "caution", "important"]
, (Div ("", ["title"], []) _ : Para ils : bs') <- bs
= blockToMarkdown' opts $ BlockQuote $
(Para (RawInline (Format "markdown") (case cls of
"note" -> "[!NOTE]\n"
"tip" -> "[!TIP]\n"
"warning" -> "[!WARNING]\n"
"caution" -> "[!CAUTION]\n"
"important" -> "[!IMPORTANT]\n"
_ -> "[!NOTE]\n") : ils)) : bs'
| otherwise = do
contents <- blockListToMarkdown opts bs
variant <- asks envVariant
return $
case () of
_ | variant == Markua ->
case () of
() | "blurb" `elem` classes'
-> prefixed "B> " contents <> blankline
| "aside" `elem` classes'
-> prefixed "A> " contents <> blankline
-- necessary to enable option to create a bibliography
| (take 3 (T.unpack id')) == "ref"
-> contents <> blankline
| otherwise -> contents <> blankline
| isEnabled Ext_fenced_divs opts &&
attrs /= nullAttr ->
let attrsToMd = if variant == Commonmark
then attrsToMarkdown opts
else classOrAttrsToMarkdown opts
divNesting = computeDivNestingLevel bs
numcolons = 3 + divNesting
colons = literal $ T.replicate numcolons ":"
in nowrap (colons <+> attrsToMd attrs) $$
chomp contents $$
colons <> blankline
| isEnabled Ext_native_divs opts ||
(isEnabled Ext_raw_html opts &&
(variant == Commonmark ||
isEnabled Ext_markdown_in_html_blocks opts)) ->
tagWithAttrs "div" attrs <> blankline <>
contents <> blankline <> "</div>" <> blankline
| isEnabled Ext_raw_html opts &&
isEnabled Ext_markdown_attribute opts ->
tagWithAttrs "div" attrs' <> blankline <>
contents <> blankline <> "</div>" <> blankline
| otherwise -> contents <> blankline
where (id',classes',kvs') = attrs
attrs' = (id',classes',("markdown","1"):kvs')
blockToMarkdown' opts (Plain inlines) = do
-- escape if para starts with ordered list marker
variant <- asks envVariant
let escapeMarker = T.concatMap $ \x -> if T.any (== x) ".()"
then T.pack ['\\', x]
else T.singleton x
let startsWithSpace (Space:_) = True
startsWithSpace (SoftBreak:_) = True
startsWithSpace _ = False
let inlines' =
if variant == PlainText
then inlines
else case inlines of
(Str t:ys)
| null ys || startsWithSpace ys
, beginsWithOrderedListMarker t
-> RawInline (Format "markdown") (escapeMarker t):ys
(Str t:_)
| t == "+" || t == "-" ||
(t == "%" && isEnabled Ext_pandoc_title_block opts &&
isEnabled Ext_all_symbols_escapable opts)
-> RawInline (Format "markdown") "\\" : inlines
_ -> inlines
contents <- inlineListToMarkdown opts inlines'
return $ contents <> cr
blockToMarkdown' opts (Para inlines) =
(<> blankline) `fmap` blockToMarkdown opts (Plain inlines)
blockToMarkdown' opts (LineBlock lns) =
if isEnabled Ext_line_blocks opts
then do
mdLines <- mapM (inlineListToMarkdown opts) lns
return $ vcat (map (hang 2 (literal "| ")) mdLines) <> blankline
else blockToMarkdown opts $ linesToPara lns
blockToMarkdown' opts b@(RawBlock f str) = do
variant <- asks envVariant
let Format fmt = f
let rawAttribBlock = return $
(literal "```{=" <> literal fmt <> "}") $$
literal str $$
(literal "```" <> literal "\n")
let renderEmpty = mempty <$ report (BlockNotRendered b)
case variant of
PlainText
| f == "plain" -> return $ literal str <> literal "\n"
Commonmark
| f `elem` ["gfm", "commonmark", "commonmark_x", "markdown"]
-> return $ literal str <> literal "\n"
| f `elem` ["html", "html5", "html4"]
-> return $ literal (removeBlankLinesInHTML str) <> literal "\n"
Markdown
| f `elem` ["markdown", "markdown_github", "markdown_phpextra",
"markdown_mmd", "markdown_strict"]
-> return $ literal str <> literal "\n"
Markua -> renderEmpty
_ | f `elem` ["html", "html5", "html4"]
, isEnabled Ext_markdown_attribute opts
-> return $ literal (addMarkdownAttribute str) <> literal "\n"
| f `elem` ["html", "html5", "html4"]
, isEnabled Ext_raw_html opts
-> return $ literal str <> literal "\n"
| f `elem` ["latex", "tex"]
, isEnabled Ext_raw_tex opts
-> return $ literal str <> literal "\n"
| isEnabled Ext_raw_attribute opts -> rawAttribBlock
_ -> renderEmpty
blockToMarkdown' opts HorizontalRule = do
variant <- asks envVariant
let indicator = case variant of
Markua -> "* * *"
_ -> T.replicate (writerColumns opts) "-"
return $ blankline <> literal indicator <> blankline
blockToMarkdown' opts (Header level attr inlines) = do
-- first, if we're putting references at the end of a section, we
-- put them here.
blkLevel <- asks envBlockLevel
refs <- if writerReferenceLocation opts == EndOfSection && blkLevel == 1
then notesAndRefs opts
else return empty
variant <- asks envVariant
-- we calculate the id that would be used by auto_identifiers
-- or gfm_auto_identifiers
-- so we know whether to print an explicit identifier
ids <- gets stIds
let autoId = uniqueIdent (writerExtensions opts) inlines ids
modify $ \st -> st{ stIds = Set.insert autoId ids }
let attr' = case attr of
("",[],[]) -> empty
(id',[],[]) | (isEnabled Ext_auto_identifiers opts
|| isEnabled Ext_gfm_auto_identifiers opts)
&& id' == autoId -> empty
(id',_,_) | isEnabled Ext_mmd_header_identifiers opts ->
space <> brackets (literal id')
_ | variant == Markua -> attrsToMarkua opts attr
| isEnabled Ext_header_attributes opts ||
isEnabled Ext_attributes opts ->
space <> attrsToMarkdown opts attr
| otherwise -> empty
contents <- inlineListToMarkdown opts $
-- ensure no newlines; see #3736
walk lineBreakToSpace $
if level == 1 && variant == PlainText &&
isEnabled Ext_gutenberg opts
then capitalize inlines
else inlines
let setext = writerSetextHeaders opts
when (not setext && isEnabled Ext_literate_haskell opts) $
report $ ATXHeadingInLHS level (render Nothing contents)
let hdr = nowrap $ case level of
1 | variant == PlainText ->
if isEnabled Ext_gutenberg opts
then blanklines 3 <> contents <> blanklines 2
else contents <> blankline
| setext ->
contents <> attr' <> cr <> literal (T.replicate (offset contents) "=") <>
blankline
2 | variant == PlainText ->
if isEnabled Ext_gutenberg opts
then blanklines 2 <> contents <> blankline
else contents <> blankline
| setext ->
contents <> attr' <> cr <> literal (T.replicate (offset contents) "-") <>
blankline
-- ghc interprets '#' characters in column 1 as linenum specifiers.
_ | variant == PlainText || isEnabled Ext_literate_haskell opts ->
contents <> blankline
_ | variant == Markua -> attr' <> cr <> literal (T.replicate level "#")
<> space <> contents <> blankline
_ -> literal (T.replicate level "#") <> space <> contents <> attr' <> blankline
return $ refs <> hdr
blockToMarkdown' opts (CodeBlock (_,classes,_) str)
| "haskell" `elem` classes && "literate" `elem` classes &&
isEnabled Ext_literate_haskell opts =
return $ prefixed "> " (literal str) <> blankline
blockToMarkdown' opts (CodeBlock attribs str) = do
variant <- asks envVariant
return $
case attribs == nullAttr of
False | variant == Commonmark ||
isEnabled Ext_backtick_code_blocks opts ->
backticks <> attrs <> cr <> literal str <> cr <> backticks <> blankline
| isEnabled Ext_fenced_code_blocks opts ->
tildes <> attrs <> cr <> literal str <> cr <> tildes <> blankline
_ | variant == Markua -> blankline <> attrsToMarkua opts attribs <> cr <> backticks <> cr <>
literal str <> cr <> backticks <> cr <> blankline
| otherwise -> nest (writerTabStop opts) (literal str) <> blankline
where
endlineLen c = maybe 3 ((+1) . maximum) $ nonEmpty
[T.length ln
| ln <- map trim (T.lines str)
, T.pack [c,c,c] `T.isPrefixOf` ln
, T.all (== c) ln]
endline c = literal $ T.replicate (endlineLen c) $ T.singleton c
backticks = endline '`'
tildes = endline '~'
attrs = if isEnabled Ext_fenced_code_attributes opts ||
isEnabled Ext_attributes opts
then nowrap $ " " <> classOrAttrsToMarkdown opts attribs
else case attribs of
(_,cls:_,_) -> " " <> literal cls
_ -> empty
blockToMarkdown' opts (BlockQuote blocks) = do
variant <- asks envVariant
-- if we're writing literate haskell, put a space before the bird tracks
-- so they won't be interpreted as lhs...
let leader
| isEnabled Ext_literate_haskell opts = " > "
| variant == PlainText = " "
| otherwise = "> "
contents <- blockListToMarkdown opts blocks
return $ prefixed leader contents <> blankline
blockToMarkdown' opts t@(Table (ident,_,_) blkCapt specs thead tbody tfoot) = do
let (caption, aligns, widths, headers, rows) = toLegacyTable blkCapt specs thead tbody tfoot
let numcols = maximum (length aligns :| length widths :
map length (headers:rows))
caption' <- inlineListToMarkdown opts caption
let caption'' = if T.null ident
then caption'
else caption' <+> attrsToMarkdown opts (ident,[],[])
let caption'''
| null caption = blankline
| isEnabled Ext_table_captions opts
= blankline $$ (": " <> caption'') $$ blankline
| otherwise = blankline $$ caption'' $$ blankline
let hasSimpleCells = onlySimpleTableCells $ headers : rows
let isSimple = hasSimpleCells && all (==0) widths
let isPlainBlock (Plain _) = True
isPlainBlock _ = False
let hasBlocks = not (all isPlainBlock $ concat . concat $ headers:rows)
let padRow r = case numcols - length r of
x | x > 0 -> r ++ replicate x empty
| otherwise -> r
let aligns' = case numcols - length aligns of
x | x > 0 -> aligns ++ replicate x AlignDefault
| otherwise -> aligns
let widths' = case numcols - length widths of
x | x > 0 -> widths ++ replicate x 0.0
| otherwise -> widths
(nst,tbl) <-
case True of
_ | isSimple &&
isEnabled Ext_simple_tables opts -> do
rawHeaders <- padRow <$> mapM (blockListToMarkdown opts) headers
rawRows <- mapM (fmap padRow . mapM (blockListToMarkdown opts))
rows
(nest 2,) <$> pandocTable opts False (all null headers)
aligns' widths' rawHeaders rawRows
| isSimple &&
isEnabled Ext_pipe_tables opts -> do
rawHeaders <- padRow <$> mapM (blockListToMarkdown opts) headers
rawRows <- mapM (fmap padRow . mapM (blockListToMarkdown opts))
rows
(id,) <$> pipeTable opts (all null headers) aligns' widths'
rawHeaders rawRows
| not hasBlocks &&
isEnabled Ext_multiline_tables opts -> do
rawHeaders <- padRow <$> mapM (blockListToMarkdown opts) headers
rawRows <- mapM (fmap padRow . mapM (blockListToMarkdown opts))
rows
(nest 2,) <$> pandocTable opts True (all null headers)
aligns' widths' rawHeaders rawRows
| isEnabled Ext_grid_tables opts &&
writerColumns opts >= 8 * numcols -> (id,) <$>
gridTable opts blockListToMarkdown
(all null headers) aligns' widths' headers rows
| hasSimpleCells &&
isEnabled Ext_pipe_tables opts -> do
rawHeaders <- padRow <$> mapM (blockListToMarkdown opts) headers
rawRows <- mapM (fmap padRow . mapM (blockListToMarkdown opts))
rows
(id,) <$> pipeTable opts (all null headers) aligns' widths'
rawHeaders rawRows
| isEnabled Ext_raw_html opts -> fmap (id,) $
literal . removeBlankLinesInHTML <$>
writeHtml5String opts{ writerTemplate = Nothing } (Pandoc nullMeta [t])
| otherwise -> return (id, literal "[TABLE]")
return $ nst (tbl $$ caption''') $$ blankline
blockToMarkdown' opts (BulletList items) = do
contents <- inList $ mapM (bulletListItemToMarkdown opts) items
return $ (if isTightList items then vcat else vsep)
contents <> blankline
blockToMarkdown' opts (OrderedList (start,sty,delim) items) = do
variant <- asks envVariant
let start' = if variant == Commonmark || isEnabled Ext_startnum opts
then start
else 1
let sty' = if isEnabled Ext_fancy_lists opts then sty else DefaultStyle
let delim' | isEnabled Ext_fancy_lists opts =
case variant of
-- Markua supports 'fancy' enumerators, but no TwoParens
Markua -> if delim == TwoParens then OneParen else delim
_ -> delim
| variant == Commonmark && --commonmark only supports one paren
(delim == OneParen || delim == TwoParens) = OneParen
| otherwise = DefaultDelim
let attribs = (start', sty', delim')
let markers = orderedListMarkers attribs
let markers' = case variant of
Markua -> markers
_ -> map (\m -> if T.length m < 3
then m <> T.replicate (3 - T.length m) " "
else m) markers
contents <- inList $
zipWithM (orderedListItemToMarkdown opts) markers' items
return $ (if isTightList items then vcat else vsep) contents <> blankline
blockToMarkdown' opts (DefinitionList items) = do
contents <- inList $ mapM (definitionListItemToMarkdown opts) items
return $ mconcat contents <> blankline
blockToMarkdown' opts (Figure figattr capt body) = do
let combinedAttr imgattr = case imgattr of
("", cls, kv) | (figid, [], []) <- figattr -> Just (figid, cls, kv)
_ -> Nothing
let combinedAlt alt = case capt of
Caption Nothing [] -> if null alt
then Just [Str "image"]
else Just alt
Caption Nothing [Plain captInlines]
| captInlines == alt || null alt -> Just captInlines
_ -> Nothing
case body of
[Plain [Image imgAttr alt (src, ttl)]]
| isEnabled Ext_implicit_figures opts
, Just descr <- combinedAlt alt
, Just imgAttr' <- combinedAttr imgAttr
, isEnabled Ext_link_attributes opts || imgAttr' == nullAttr
-> do
-- use implicit figures if possible
let tgt' = (src, fromMaybe ttl $ T.stripPrefix "fig:" ttl)
contents <- inlineListToMarkdown opts [Image imgAttr' descr tgt']
return $ contents <> blankline
_ ->
-- fallback to raw html if possible or div otherwise
if isEnabled Ext_raw_html opts
then figureToMarkdown opts figattr capt body
else blockToMarkdown' opts $ figureDiv figattr capt body
inList :: Monad m => MD m a -> MD m a
inList p = local (\env -> env {envInList = True}) p
addMarkdownAttribute :: Text -> Text
addMarkdownAttribute s =
case span isTagText $ reverse $ parseTags s of
(xs, TagOpen t attrs:rest) ->
renderTags' $ reverse rest ++ (TagOpen t attrs' : reverse xs)
where attrs' = ("markdown","1"):[(x,y) | (x,y) <- attrs,
x /= "markdown"]
_ -> s
-- | Converts a figure to Markdown by wrapping it in a div named `figure`.
figureToMarkdown :: PandocMonad m
=> WriterOptions
-> Attr
-> Caption
-> [Block]
-> MD m (Doc Text)
figureToMarkdown opts attr@(ident, classes, kvs) capt body
| isEnabled Ext_raw_html opts =
(<> blankline) . literal . T.strip <$>
writeHtml5String
opts{ writerTemplate = Nothing }
(Pandoc nullMeta [Figure attr capt body])
| otherwise = let attr' = (ident, ["figure"] `union` classes, kvs)
in blockToMarkdown' opts (Div attr' body)
itemEndsWithTightList :: [Block] -> Bool
itemEndsWithTightList bs =
case bs of
[Plain _, BulletList xs] -> isTightList xs
[Plain _, OrderedList _ xs] -> isTightList xs
_ -> False
-- | Convert bullet list item (list of blocks) to markdown.
bulletListItemToMarkdown :: PandocMonad m => WriterOptions -> [Block] -> MD m (Doc Text)
bulletListItemToMarkdown opts bs = do
variant <- asks envVariant
let exts = writerExtensions opts
contents <- blockListToMarkdown opts $ taskListItemToAscii exts bs
let start = case variant of
Markua -> "* "
Commonmark -> "- "
_ -> "- " <> T.replicate (writerTabStop opts - 2) " "
-- remove trailing blank line if item ends with a tight list
let contents' = if itemEndsWithTightList bs
then chomp contents <> cr
else contents
return $ hang (T.length start) (literal start) contents'
-- | Convert ordered list item (a list of blocks) to markdown.
orderedListItemToMarkdown :: PandocMonad m
=> WriterOptions -- ^ options
-> Text -- ^ list item marker
-> [Block] -- ^ list item (list of blocks)
-> MD m (Doc Text)
orderedListItemToMarkdown opts marker bs = do
let exts = writerExtensions opts
contents <- blockListToMarkdown opts $ taskListItemToAscii exts bs
variant <- asks envVariant
let sps = case writerTabStop opts - T.length marker of
n | n > 0 -> literal $ T.replicate n " "
_ -> literal " "
let ind = if isEnabled Ext_four_space_rule opts
then writerTabStop opts
else max (writerTabStop opts) (T.length marker + 1)
let start = case variant of
Markua -> literal marker <> " "
_ -> literal marker <> sps
-- remove trailing blank line if item ends with a tight list
let contents' = if itemEndsWithTightList bs
then chomp contents <> cr
else contents
return $ hang ind start contents'
-- | Convert definition list item (label, list of blocks) to markdown.
definitionListItemToMarkdown :: PandocMonad m
=> WriterOptions
-> ([Inline],[[Block]])
-> MD m (Doc Text)
definitionListItemToMarkdown opts (label, defs) = do
labelText <- blockToMarkdown opts (Plain label)
defs' <- mapM (mapM (blockToMarkdown opts)) defs
if isEnabled Ext_definition_lists opts
then do
let tabStop = writerTabStop opts
variant <- asks envVariant
let leader = case variant of
PlainText -> " "
Markua -> ":"
_ -> ": "
let sps = case writerTabStop opts - 3 of
n | n > 0 -> literal $ T.replicate n " "
_ -> literal " "
let isTight = case defs of
((Plain _ : _): _) -> True
_ -> False
if isEnabled Ext_compact_definition_lists opts
then do
let contents = vcat $ map (\d -> hang tabStop (leader <> sps)
$ vcat d <> cr) defs'
return $ nowrap labelText <> cr <> contents <> cr
else do
let contents = (if isTight then vcat else vsep) $ map
(\d -> hang tabStop (leader <> sps) $ vcat d)
defs'
return $ blankline <> nowrap labelText $$
(if isTight then empty else blankline) <> contents <> blankline
else
return $ nowrap (chomp labelText <> literal " " <> cr) <>
vsep (map vsep defs') <> blankline
-- | Convert list of Pandoc block elements to markdown.
blockListToMarkdown :: PandocMonad m
=> WriterOptions -- ^ Options
-> [Block] -- ^ List of block elements
-> MD m (Doc Text)
blockListToMarkdown opts blocks = do
inlist <- asks envInList
variant <- asks envVariant
-- a) insert comment between list and indented code block, or the
-- code block will be treated as a list continuation paragraph
-- b) change Plain to Para unless it's followed by a RawBlock
-- or has a list as its parent (#3487)
let fixBlocks (b : CodeBlock attr x : rest)
| (not (variant == Commonmark ||
isEnabled Ext_backtick_code_blocks opts ||
isEnabled Ext_fenced_code_blocks opts) ||
attr == nullAttr)
&& isListBlock b
= b : commentSep : CodeBlock attr x : fixBlocks rest
fixBlocks (b1@(BulletList _) : b2@(BulletList _) : bs) =
b1 : commentSep : fixBlocks (b2:bs)
fixBlocks (b1@(OrderedList _ _) : b2@(OrderedList _ _) : bs) =
b1 : commentSep : fixBlocks (b2:bs)
fixBlocks (b1@(DefinitionList _) : b2@(DefinitionList _) : bs) =
b1 : commentSep : fixBlocks (b2:bs)
fixBlocks (Plain ils : bs@(RawBlock{}:_)) =
Plain ils : fixBlocks bs
fixBlocks (Plain ils : bs@(Div{}:_))
| isEnabled Ext_fenced_divs opts =
Para ils : fixBlocks bs
fixBlocks (Plain ils : bs) | inlist =
Plain ils : fixBlocks bs
fixBlocks (Plain ils : bs) =
Para ils : fixBlocks bs
fixBlocks (r@(RawBlock f raw) : b : bs)
| not (T.null raw)
, T.last raw /= '\n' =
case b of
Plain{} -> r : fixBlocks (b:bs)
RawBlock{} -> r : fixBlocks (b:bs)
_ -> RawBlock f (raw <> "\n") : fixBlocks (b:bs) -- #4629
fixBlocks (x : xs) = x : fixBlocks xs
fixBlocks [] = []
isListBlock (BulletList _) = True
isListBlock (OrderedList _ _) = True
isListBlock (DefinitionList _) = True
isListBlock _ = False
commentSep
| variant == PlainText = Plain []
| variant == Markua = Plain []
| isEnabled Ext_raw_html opts = RawBlock "html" "<!-- -->\n"
| otherwise = RawBlock "markdown" " \n"
mconcat <$> mapM (blockToMarkdown opts) (fixBlocks blocks)
lineBreakToSpace :: Inline -> Inline
lineBreakToSpace LineBreak = Space
lineBreakToSpace SoftBreak = Space
lineBreakToSpace x = x
removeBlankLinesInHTML :: Text -> Text
removeBlankLinesInHTML = T.pack . go False . T.unpack
where go _ [] = []
go True ('\n':cs) = " " <> go False cs
go False ('\n':cs) = '\n' : go True cs
go !afternewline (!c:cs)
| isSpace c = c : go afternewline cs
| otherwise = c : go False cs
computeDivNestingLevel :: [Block] -> Int
computeDivNestingLevel = foldr go 0
where
go (Div _ bls') n = max (n + 1) (foldr go (n + 1) bls')
go _ n = n