Added Text.Pandoc.Readers.Groff.

This is an internal module that exports a tokenizer for groff
formats.

Closes #4998.

3 files changed, 531 insertions, 465 deletions

diff --git a/pandoc.cabal b/pandoc.cabal
index ecb4aa766..9480753ff 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -534,6 +534,7 @@ library
                    Text.Pandoc.Readers.Org.ParserState,
                    Text.Pandoc.Readers.Org.Parsing,
                    Text.Pandoc.Readers.Org.Shared,
+                   Text.Pandoc.Readers.Groff,
                    Text.Pandoc.Writers.Groff,
                    Text.Pandoc.Writers.Powerpoint.Presentation,
                    Text.Pandoc.Writers.Powerpoint.Output,
diff --git a/src/Text/Pandoc/Readers/Groff.hs b/src/Text/Pandoc/Readers/Groff.hs
new file mode 100644
index 000000000..90ae8561a
--- /dev/null
+++ b/src/Text/Pandoc/Readers/Groff.hs
@@ -0,0 +1,524 @@
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-
+  Copyright (C) 2018 Yan Pashkovsky <yanp.bugz@gmail.com>
+                     and 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.Readers.Groff
+   Copyright   : Copyright (C) 2018 Yan Pashkovsky and John MacFarlane
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Yan Pashkovsky <yanp.bugz@gmail.com>
+   Stability   : WIP
+   Portability : portable
+
+Tokenizer for groff formats (man, ms).
+-}
+module Text.Pandoc.Readers.Groff
+  ( FontKind(..)
+  , Font
+  , MacroKind
+  , LinePart(..)
+  , Arg
+  , ManToken(..)
+  , ManTokens(..)
+  , singleTok
+  , RoffState(..)
+  , ManLexer
+  , manToken
+  , linePartsToString
+  )
+where
+
+import Prelude
+import Control.Monad (void, mzero, guard, when)
+import Text.Pandoc.Class
+       (getResourcePath, readFileFromDirs, PandocMonad(..), report)
+import Data.Char (isHexDigit, chr, ord, isAscii, isAlphaNum, isSpace)
+import Data.Default (Default)
+import qualified Data.Map as M
+import Data.Set (Set)
+import qualified Data.Set as S
+import Data.List (intercalate, isSuffixOf)
+import qualified Data.Text as T
+import Text.Pandoc.Builder as B
+import Text.Pandoc.Logging (LogMessage(..))
+import Text.Pandoc.Options
+import Text.Pandoc.Parsing
+import Text.Pandoc.Shared (safeRead)
+import Text.Parsec hiding (tokenPrim)
+import qualified Text.Parsec as Parsec
+import Text.Pandoc.GroffChar (characterCodes, combiningAccents)
+import qualified Data.Sequence as Seq
+import qualified Data.Foldable as Foldable
+import qualified Data.Text.Normalize as Normalize
+
+-- import Debug.Trace (traceShowId)
+
+--
+-- Data Types
+--
+data FontKind = Bold | Italic | Monospace | Regular deriving (Show, Eq, Ord)
+
+type MacroKind = String
+
+type Font = Set FontKind
+
+data LinePart = RoffStr (String, Font)
+              | MacroArg Int
+              deriving Show
+
+type Arg = [LinePart]
+
+-- TODO parse tables (see man tbl)
+data ManToken = MLine [LinePart]
+              | MEmptyLine
+              | MMacro MacroKind [Arg] SourcePos
+              | MTable [Alignment] ManTokens [ManTokens] [[ManTokens]]
+              deriving Show
+
+newtype ManTokens = ManTokens { unManTokens :: Seq.Seq ManToken }
+        deriving (Show, Semigroup, Monoid)
+
+singleTok :: ManToken -> ManTokens
+singleTok t = ManTokens (Seq.singleton t)
+
+data RoffState = RoffState { fontKind      :: Font
+                           , customMacros  :: M.Map String ManTokens
+                           } deriving Show
+
+instance Default RoffState where
+  def = RoffState { customMacros = M.fromList
+                       $ map (\(n, s) ->
+                                (n, singleTok
+                                  (MLine [RoffStr (s, mempty)])))
+                       [ ("Tm", "\x2122")
+                       , ("lq", "\x201C")
+                       , ("rq", "\x201D")
+                       , ("R",  "\x00AE") ]
+                  , fontKind     = S.singleton Regular }
+
+type ManLexer m = ParserT [Char] RoffState m
+
+--
+-- Lexer: String -> ManToken
+--
+
+eofline :: Stream s m Char => ParsecT s u m ()
+eofline = void newline <|> eof
+
+spacetab :: Stream s m Char => ParsecT s u m Char
+spacetab = char ' ' <|> char '\t'
+
+characterCodeMap :: M.Map String Char
+characterCodeMap =
+  M.fromList $ map (\(x,y) -> (y,x)) characterCodes
+
+combiningAccentsMap :: M.Map String Char
+combiningAccentsMap =
+  M.fromList $ map (\(x,y) -> (y,x)) combiningAccents
+
+escapeLexer :: PandocMonad m => ManLexer m String
+escapeLexer = try $ do
+  char '\\'
+  c <- noneOf ['*','$'] -- see escStar, macroArg
+  case c of
+    '(' -> twoCharGlyph
+    '[' -> bracketedGlyph
+    'f' -> escFont
+    's' -> escFontSize
+    '"' -> mempty <$ skipMany (satisfy (/='\n')) -- line comment
+    '#' -> mempty <$ manyTill anyChar newline
+    '%' -> return mempty
+    '{' -> return mempty
+    '}' -> return mempty
+    '&' -> return mempty
+    '\n' -> return mempty
+    ':' -> return mempty
+    '0' -> return mempty
+    'c' -> return mempty
+    '-' -> return "-"
+    '_' -> return "_"
+    ' ' -> return " "
+    '\\' -> return "\\"
+    't' -> return "\t"
+    'e' -> return "\\"
+    '`' -> return "`"
+    '^' -> return " "
+    '|' -> return " "
+    '\'' -> return "`"
+    '.' -> return "`"
+    '~' -> return "\160" -- nonbreaking space
+    _   -> escUnknown ['\\',c] "\xFFFD"
+
+  where
+
+  twoCharGlyph = do
+    cs <- count 2 anyChar
+    case M.lookup cs characterCodeMap of
+      Just c  -> return [c]
+      Nothing -> escUnknown ('\\':'(':cs) "\xFFFD"
+
+  bracketedGlyph = unicodeGlyph <|> charGlyph
+
+  charGlyph = do
+    cs <- manyTill (noneOf ['[',']','\n']) (char ']')
+    (case words cs of
+        []  -> mzero
+        [s] -> case M.lookup s characterCodeMap of
+                 Nothing -> mzero
+                 Just c  -> return [c]
+        (s:ss) -> do
+          basechar <- case M.lookup cs characterCodeMap of
+                        Nothing ->
+                          case s of
+                            [ch] | isAscii ch && isAlphaNum ch ->
+                                   return ch
+                            _ -> mzero
+                        Just c  -> return c
+          let addAccents [] xs = return $ T.unpack .
+                                   Normalize.normalize Normalize.NFC .
+                                   T.pack $ reverse xs
+              addAccents (a:as) xs =
+                case M.lookup a combiningAccentsMap of
+                  Just x  -> addAccents as (x:xs)
+                  Nothing -> mzero
+          addAccents ss [basechar])
+      <|> escUnknown ("\\[" ++ cs ++ "]") "\xFFFD"
+
+  unicodeGlyph = try $ ucharCode `sepBy1` (char '_') <* char ']'
+
+  ucharCode = try $ do
+    char 'u'
+    cs <- many1 (satisfy isHexDigit)
+    let lcs = length cs
+    guard $ lcs >= 4 && lcs <= 6
+    case chr <$> safeRead ('0':'x':cs) of
+       Nothing  -> mzero
+       Just c   -> return c
+
+  -- \s-1 \s0 -- we ignore these
+  escFontSize :: PandocMonad m => ManLexer m String
+  escFontSize = do
+    pos <- getPosition
+    pm <- option "" $ count 1 (oneOf "+-")
+    ds <- many1 digit
+    report $ SkippedContent ("\\s" ++ pm ++ ds) pos
+    return mempty
+
+  escFont :: PandocMonad m => ManLexer m String
+  escFont = do
+    font <- choice
+          [ S.singleton <$> letterFontKind
+          , char '(' >> anyChar >> anyChar >> return (S.singleton Regular)
+          , char 'S' >> return (S.singleton Regular)
+          , try lettersFont
+          , digit >> return (S.singleton Regular)
+          ]
+    modifyState (\r -> r {fontKind = font})
+    return mempty
+
+  lettersFont :: PandocMonad m => ManLexer m Font
+  lettersFont = do
+    char '['
+    fs <- many letterFontKind
+    skipMany letter
+    char ']'
+    return $ S.fromList fs
+
+  letterFontKind :: PandocMonad m => ManLexer m FontKind
+  letterFontKind = choice [
+      oneOf ['B','b'] >> return Bold
+    , oneOf ['I','i'] >> return Italic
+    , oneOf ['C','c'] >> return Monospace
+    , oneOf ['P','p','R','r'] >> return Regular
+    ]
+
+  escUnknown :: PandocMonad m => String -> a -> ManLexer m a
+  escUnknown s x = do
+    pos <- getPosition
+    report $ SkippedContent ("Unknown escape sequence " ++ s) pos
+    return x
+
+currentFont :: PandocMonad m => ManLexer m Font
+currentFont = fontKind <$> getState
+
+-- separate function from lexMacro since real man files sometimes do not follow the rules
+lexComment :: PandocMonad m => ManLexer m ManTokens
+lexComment = do
+  try $ string ".\\\""
+  many Parsec.space
+  skipMany $ noneOf "\n"
+  char '\n'
+  return mempty
+
+lexMacro :: PandocMonad m => ManLexer m ManTokens
+lexMacro = do
+  pos <- getPosition
+  char '.' <|> char '\''
+  many spacetab
+  macroName <- many (satisfy (not . isSpace))
+  case macroName of
+    "nop" -> return mempty
+    "ie"  -> lexConditional
+    "if"  -> lexConditional
+    "el"  -> skipConditional
+    "TS"  -> lexTable
+
+    _ -> do
+       args <- lexArgs
+       case macroName of
+         ""     -> return mempty
+         "\\\"" -> return mempty
+         "\\#"  -> return mempty
+         "de"   -> lexMacroDef args
+         "de1"  -> lexMacroDef args
+         "ds"   -> lexStringDef args
+         "ds1"  -> lexStringDef args
+         "sp"   -> return $ singleTok MEmptyLine
+         "so"   -> lexIncludeFile args
+         _      -> resolveMacro macroName args pos
+
+-- | TODO placeholder
+lexTable :: PandocMonad m => ManLexer m ManTokens
+lexTable = do
+  pos <- getPosition
+  manyTill anyLine (try (string ".TE" >> many spacetab >> eofline))
+  report $ SkippedContent "table" pos
+  return mempty
+
+-- We don't fully handle the conditional.  But we do
+-- include everything under '.ie n', which occurs commonly
+-- in man pages.  We always skip the '.el' part.
+lexConditional :: PandocMonad m => ManLexer m ManTokens
+lexConditional = do
+  skipMany spacetab
+  parseNCond <|> skipConditional
+
+-- n means nroff mode
+parseNCond :: PandocMonad m => ManLexer m ManTokens
+parseNCond = do
+  char '\n'
+  many1 spacetab
+  lexGroup <|> manToken
+
+lexGroup :: PandocMonad m => ManLexer m ManTokens
+lexGroup = do
+  groupstart
+  mconcat <$> manyTill manToken groupend
+  where
+    groupstart = try $ string "\\{\\" >> newline
+    groupend   = try $ string "\\}" >> eofline
+
+skipConditional :: PandocMonad m => ManLexer m ManTokens
+skipConditional = do
+  rest <- anyLine
+  when ("\\{\\" `isSuffixOf` rest) $
+    void $ manyTill anyChar (try (string "\\}"))
+  return mempty
+
+lexIncludeFile :: PandocMonad m => [Arg] -> ManLexer m ManTokens
+lexIncludeFile args = do
+  pos <- getPosition
+  case args of
+    (f:_) -> do
+      let fp = linePartsToString f
+      dirs <- getResourcePath
+      result <- readFileFromDirs dirs fp
+      case result of
+        Nothing  -> report $ CouldNotLoadIncludeFile fp pos
+        Just s   -> getInput >>= setInput . (s ++)
+      return mempty
+    []    -> return mempty
+
+resolveMacro :: PandocMonad m
+             => String -> [Arg] -> SourcePos -> ManLexer m ManTokens
+resolveMacro macroName args pos = do
+  macros <- customMacros <$> getState
+  case M.lookup macroName macros of
+    Nothing -> return $ singleTok $ MMacro macroName args pos
+    Just ts -> do
+      let fillLP (RoffStr (x,y)) zs = RoffStr (x,y) : zs
+          fillLP (MacroArg i)    zs =
+            case drop (i - 1) args of
+              []     -> zs
+              (ys:_) -> ys ++ zs
+      let fillMacroArg (MLine lineparts) =
+            MLine (foldr fillLP [] lineparts)
+          fillMacroArg x = x
+      return $ ManTokens . fmap fillMacroArg . unManTokens $ ts
+
+lexStringDef :: PandocMonad m => [Arg] -> ManLexer m ManTokens
+lexStringDef args = do -- string definition
+   case args of
+     []     -> fail "No argument to .ds"
+     (x:ys) -> do
+       let ts = singleTok $ MLine (intercalate [RoffStr (" ", mempty)] ys)
+       let stringName = linePartsToString x
+       modifyState $ \st ->
+         st{ customMacros = M.insert stringName ts (customMacros st) }
+   return mempty
+
+lexMacroDef :: PandocMonad m => [Arg] -> ManLexer m ManTokens
+lexMacroDef args = do -- macro definition
+   (macroName, stopMacro) <-
+     case args of
+       (x : y : _) -> return (linePartsToString x, linePartsToString y)
+                      -- optional second arg
+       (x:_)       -> return (linePartsToString x, ".")
+       []          -> fail "No argument to .de"
+   let stop = try $ do
+         char '.' <|> char '\''
+         many spacetab
+         string stopMacro
+         _ <- lexArgs
+         return ()
+   ts <- mconcat <$> manyTill manToken stop
+   modifyState $ \st ->
+     st{ customMacros = M.insert macroName ts (customMacros st) }
+   return mempty
+
+lexArgs :: PandocMonad m => ManLexer m [Arg]
+lexArgs = do
+  args <- many $ try oneArg
+  skipMany spacetab
+  eofline
+  return args
+
+  where
+
+  oneArg :: PandocMonad m => ManLexer m [LinePart]
+  oneArg = do
+    skipMany $ try $ string "\\\n"  -- continuation line
+    try quotedArg <|> plainArg
+    -- try, because there are some erroneous files, e.g. linux/bpf.2
+
+  plainArg :: PandocMonad m => ManLexer m [LinePart]
+  plainArg = do
+    skipMany spacetab
+    mconcat <$> many1
+      (macroArg <|> esc <|> regularText <|> unescapedQuote <|> escStar)
+    where
+      unescapedQuote = do
+         char '"'
+         fonts <- currentFont
+         return [RoffStr ("\"", fonts)]
+
+
+  quotedArg :: PandocMonad m => ManLexer m [LinePart]
+  quotedArg = do
+    skipMany spacetab
+    char '"'
+    xs <- mconcat <$>
+           many (macroArg <|> esc <|> escStar <|> regularText
+                 <|> spaceTabChar <|> escapedQuote)
+    char '"'
+    return xs
+    where
+      escapedQuote = try $ do
+        char '"'
+        char '"'
+        fonts <- currentFont
+        return [RoffStr ("\"", fonts)]
+
+escStar :: PandocMonad m => ManLexer m [LinePart]
+escStar = try $ do
+  pos <- getPosition
+  char '\\'
+  char '*'
+  c <- anyChar
+  case c of
+    '(' -> do
+      cs <- count 2 anyChar
+      resolveString cs pos
+    '[' -> do
+      cs <- many (noneOf "\t\n\r ]")
+      char ']'
+      resolveString cs pos
+    'S' -> return mempty -- switch back to default font size
+    _   -> resolveString [c] pos
+
+  where
+
+  -- strings and macros share namespace
+  resolveString stringname pos = do
+    ManTokens ts <- resolveMacro stringname [] pos
+    case Foldable.toList ts of
+      [MLine xs] -> return xs
+      _          -> do
+        report $ SkippedContent ("unknown string " ++ stringname) pos
+        return mempty
+
+lexLine :: PandocMonad m => ManLexer m ManTokens
+lexLine = do
+  lnparts <- mconcat <$> many1 linePart
+  eofline
+  go lnparts
+  where  -- return empty line if we only have empty strings;
+         -- this can happen if the line just contains \f[C], for example.
+    go [] = return mempty
+    go (RoffStr ("",_):xs) = go xs
+    go xs = return $ singleTok $ MLine xs
+
+linePart :: PandocMonad m => ManLexer m [LinePart]
+linePart = macroArg <|> esc <|> escStar <|>
+           regularText <|> quoteChar <|> spaceTabChar
+
+macroArg :: PandocMonad m => ManLexer m [LinePart]
+macroArg = try $ do
+  string "\\\\$"
+  x <- digit
+  return [MacroArg $ ord x - ord '0']
+
+esc :: PandocMonad m => ManLexer m [LinePart]
+esc = do
+  s <- escapeLexer
+  font <- currentFont
+  return [RoffStr (s, font)]
+
+regularText :: PandocMonad m => ManLexer m [LinePart]
+regularText = do
+  s <- many1 $ noneOf "\n\r\t \\\""
+  font <- currentFont
+  return [RoffStr (s, font)]
+
+quoteChar :: PandocMonad m => ManLexer m [LinePart]
+quoteChar = do
+  char '"'
+  font <- currentFont
+  return [RoffStr ("\"", font)]
+
+spaceTabChar :: PandocMonad m => ManLexer m [LinePart]
+spaceTabChar = do
+  c <- spacetab
+  font <- currentFont
+  return [RoffStr ([c], font)]
+
+lexEmptyLine :: PandocMonad m => ManLexer m ManTokens
+lexEmptyLine = char '\n' >> return (singleTok MEmptyLine)
+
+manToken :: PandocMonad m => ManLexer m ManTokens
+manToken = lexComment <|> lexMacro <|> lexLine <|> lexEmptyLine
+
+linePartsToString :: [LinePart] -> String
+linePartsToString = mconcat . map go
+  where
+  go (RoffStr (s, _)) = s
+  go _ = mempty
diff --git a/src/Text/Pandoc/Readers/Man.hs b/src/Text/Pandoc/Readers/Man.hs
index f3013be5f..50ec0c019 100644
--- a/src/Text/Pandoc/Readers/Man.hs
+++ b/src/Text/Pandoc/Readers/Man.hs
@@ -18,8 +18,6 @@ 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
 
-
-
 -}
 
 {- |
@@ -36,76 +34,25 @@ Conversion of man to 'Pandoc' document.
 module Text.Pandoc.Readers.Man (readMan) where
 
 import Prelude
-import Control.Monad (liftM, void, mzero, guard, when)
-import Control.Monad.Except (throwError)
-import Text.Pandoc.Class
-       (getResourcePath, readFileFromDirs, PandocMonad(..), report)
-import Data.Char (isHexDigit, chr, ord, isAscii, isAlphaNum, isSpace)
 import Data.Default (Default)
+import Control.Monad (liftM, mzero, guard)
+import Control.Monad.Except (throwError)
+import Text.Pandoc.Class (PandocMonad(..), report)
 import Data.Maybe (catMaybes)
-import qualified Data.Map as M
-import Data.Set (Set)
 import qualified Data.Set as S
-import Data.List (intersperse, intercalate, isSuffixOf)
+import Data.List (intersperse, intercalate)
 import qualified Data.Text as T
 import Text.Pandoc.Builder as B
 import Text.Pandoc.Error (PandocError (PandocParsecError))
 import Text.Pandoc.Logging (LogMessage(..))
 import Text.Pandoc.Options
 import Text.Pandoc.Parsing
-import Text.Pandoc.Shared (crFilter, safeRead)
+import Text.Pandoc.Shared (crFilter)
+import Text.Pandoc.Readers.Groff  -- TODO explicit imports
 import Text.Parsec hiding (tokenPrim)
 import qualified Text.Parsec as Parsec
 import Text.Parsec.Pos (updatePosString)
-import Text.Pandoc.GroffChar (characterCodes, combiningAccents)
-import qualified Data.Sequence as Seq
 import qualified Data.Foldable as Foldable
-import qualified Data.Text.Normalize as Normalize
-
--- import Debug.Trace (traceShowId)
-
---
--- Data Types
---
-data FontKind = Bold | Italic | Monospace | Regular deriving (Show, Eq, Ord)
-
-type MacroKind = String
-
-type Font = Set FontKind
-
-data LinePart = RoffStr (String, Font)
-              | MacroArg Int
-              deriving Show
-
-type Arg = [LinePart]
-
--- TODO parse tables (see man tbl)
-data ManToken = MLine [LinePart]
-              | MEmptyLine
-              | MMacro MacroKind [Arg] SourcePos
-              | MTable [Alignment] ManTokens [ManTokens] [[ManTokens]]
-              deriving Show
-
-newtype ManTokens = ManTokens { unManTokens :: Seq.Seq ManToken }
-        deriving (Show, Semigroup, Monoid)
-
-singleTok :: ManToken -> ManTokens
-singleTok t = ManTokens (Seq.singleton t)
-
-data RoffState = RoffState { fontKind      :: Font
-                           , customMacros  :: M.Map String ManTokens
-                           } deriving Show
-
-instance Default RoffState where
-  def = RoffState { customMacros = M.fromList
-                       $ map (\(n, s) ->
-                                (n, singleTok
-                                  (MLine [RoffStr (s, mempty)])))
-                       [ ("Tm", "\x2122")
-                       , ("lq", "\x201C")
-                       , ("rq", "\x201D")
-                       , ("R",  "\x00AE") ]
-                  , fontKind     = S.singleton Regular }
 
 data ManState = ManState { readerOptions :: ReaderOptions
                          , metadata      :: Meta
@@ -115,7 +62,6 @@ instance Default ManState where
   def = ManState { readerOptions = def
                  , metadata      = nullMeta }
 
-type ManLexer m = ParserT [Char] RoffState m
 type ManParser m = ParserT [ManToken] ManState m
 
 
@@ -147,405 +93,6 @@ readMan opts txt = do
   mapLeft f (Left x) = Left $ f x
   mapLeft _ (Right r) = Right r
 
---
--- Lexer: String -> ManToken
---
-
-eofline :: Stream s m Char => ParsecT s u m ()
-eofline = void newline <|> eof
-
-spacetab :: Stream s m Char => ParsecT s u m Char
-spacetab = char ' ' <|> char '\t'
-
-characterCodeMap :: M.Map String Char
-characterCodeMap =
-  M.fromList $ map (\(x,y) -> (y,x)) characterCodes
-
-combiningAccentsMap :: M.Map String Char
-combiningAccentsMap =
-  M.fromList $ map (\(x,y) -> (y,x)) combiningAccents
-
-escapeLexer :: PandocMonad m => ManLexer m String
-escapeLexer = try $ do
-  char '\\'
-  c <- noneOf ['*','$'] -- see escStar, macroArg
-  case c of
-    '(' -> twoCharGlyph
-    '[' -> bracketedGlyph
-    'f' -> escFont
-    's' -> escFontSize
-    '"' -> mempty <$ skipMany (satisfy (/='\n')) -- line comment
-    '#' -> mempty <$ manyTill anyChar newline
-    '%' -> return mempty
-    '{' -> return mempty
-    '}' -> return mempty
-    '&' -> return mempty
-    '\n' -> return mempty
-    ':' -> return mempty
-    '0' -> return mempty
-    'c' -> return mempty
-    '-' -> return "-"
-    '_' -> return "_"
-    ' ' -> return " "
-    '\\' -> return "\\"
-    't' -> return "\t"
-    'e' -> return "\\"
-    '`' -> return "`"
-    '^' -> return " "
-    '|' -> return " "
-    '\'' -> return "`"
-    '.' -> return "`"
-    '~' -> return "\160" -- nonbreaking space
-    _   -> escUnknown ['\\',c] "\xFFFD"
-
-  where
-
-  twoCharGlyph = do
-    cs <- count 2 anyChar
-    case M.lookup cs characterCodeMap of
-      Just c  -> return [c]
-      Nothing -> escUnknown ('\\':'(':cs) "\xFFFD"
-
-  bracketedGlyph = unicodeGlyph <|> charGlyph
-
-  charGlyph = do
-    cs <- manyTill (noneOf ['[',']','\n']) (char ']')
-    (case words cs of
-        []  -> mzero
-        [s] -> case M.lookup s characterCodeMap of
-                 Nothing -> mzero
-                 Just c  -> return [c]
-        (s:ss) -> do
-          basechar <- case M.lookup cs characterCodeMap of
-                        Nothing ->
-                          case s of
-                            [ch] | isAscii ch && isAlphaNum ch ->
-                                   return ch
-                            _ -> mzero
-                        Just c  -> return c
-          let addAccents [] xs = return $ T.unpack .
-                                   Normalize.normalize Normalize.NFC .
-                                   T.pack $ reverse xs
-              addAccents (a:as) xs =
-                case M.lookup a combiningAccentsMap of
-                  Just x  -> addAccents as (x:xs)
-                  Nothing -> mzero
-          addAccents ss [basechar])
-      <|> escUnknown ("\\[" ++ cs ++ "]") "\xFFFD"
-
-  unicodeGlyph = try $ ucharCode `sepBy1` (char '_') <* char ']'
-
-  ucharCode = try $ do
-    char 'u'
-    cs <- many1 (satisfy isHexDigit)
-    let lcs = length cs
-    guard $ lcs >= 4 && lcs <= 6
-    case chr <$> safeRead ('0':'x':cs) of
-       Nothing  -> mzero
-       Just c   -> return c
-
-  -- \s-1 \s0 -- we ignore these
-  escFontSize :: PandocMonad m => ManLexer m String
-  escFontSize = do
-    pos <- getPosition
-    pm <- option "" $ count 1 (oneOf "+-")
-    ds <- many1 digit
-    report $ SkippedContent ("\\s" ++ pm ++ ds) pos
-    return mempty
-
-  escFont :: PandocMonad m => ManLexer m String
-  escFont = do
-    font <- choice
-          [ S.singleton <$> letterFontKind
-          , char '(' >> anyChar >> anyChar >> return (S.singleton Regular)
-          , char 'S' >> return (S.singleton Regular)
-          , try lettersFont
-          , digit >> return (S.singleton Regular)
-          ]
-    modifyState (\r -> r {fontKind = font})
-    return mempty
-
-  lettersFont :: PandocMonad m => ManLexer m Font
-  lettersFont = do
-    char '['
-    fs <- many letterFontKind
-    skipMany letter
-    char ']'
-    return $ S.fromList fs
-
-  letterFontKind :: PandocMonad m => ManLexer m FontKind
-  letterFontKind = choice [
-      oneOf ['B','b'] >> return Bold
-    , oneOf ['I','i'] >> return Italic
-    , oneOf ['C','c'] >> return Monospace
-    , oneOf ['P','p','R','r'] >> return Regular
-    ]
-
-  escUnknown :: PandocMonad m => String -> a -> ManLexer m a
-  escUnknown s x = do
-    pos <- getPosition
-    report $ SkippedContent ("Unknown escape sequence " ++ s) pos
-    return x
-
-currentFont :: PandocMonad m => ManLexer m Font
-currentFont = fontKind <$> getState
-
--- separate function from lexMacro since real man files sometimes do not follow the rules
-lexComment :: PandocMonad m => ManLexer m ManTokens
-lexComment = do
-  try $ string ".\\\""
-  many Parsec.space
-  skipMany $ noneOf "\n"
-  char '\n'
-  return mempty
-
-lexMacro :: PandocMonad m => ManLexer m ManTokens
-lexMacro = do
-  pos <- getPosition
-  char '.' <|> char '\''
-  many spacetab
-  macroName <- many (satisfy (not . isSpace))
-  case macroName of
-    "nop" -> return mempty
-    "ie"  -> lexConditional
-    "if"  -> lexConditional
-    "el"  -> skipConditional
-    "TS"  -> lexTable
-
-    _ -> do
-       args <- lexArgs
-       case macroName of
-         ""     -> return mempty
-         "\\\"" -> return mempty
-         "\\#"  -> return mempty
-         "de"   -> lexMacroDef args
-         "de1"  -> lexMacroDef args
-         "ds"   -> lexStringDef args
-         "ds1"  -> lexStringDef args
-         "sp"   -> return $ singleTok MEmptyLine
-         "so"   -> lexIncludeFile args
-         _      -> resolveMacro macroName args pos
-
--- | TODO placeholder
-lexTable :: PandocMonad m => ManLexer m ManTokens
-lexTable = do
-  pos <- getPosition
-  manyTill anyLine (try (string ".TE" >> many spacetab >> eofline))
-  report $ SkippedContent "table" pos
-  return mempty
-
--- We don't fully handle the conditional.  But we do
--- include everything under '.ie n', which occurs commonly
--- in man pages.  We always skip the '.el' part.
-lexConditional :: PandocMonad m => ManLexer m ManTokens
-lexConditional = do
-  skipMany spacetab
-  parseNCond <|> skipConditional
-
--- n means nroff mode
-parseNCond :: PandocMonad m => ManLexer m ManTokens
-parseNCond = do
-  char '\n'
-  many1 spacetab
-  lexGroup <|> manToken
-
-lexGroup :: PandocMonad m => ManLexer m ManTokens
-lexGroup = do
-  groupstart
-  mconcat <$> manyTill manToken groupend
-  where
-    groupstart = try $ string "\\{\\" >> newline
-    groupend   = try $ string "\\}" >> eofline
-
-skipConditional :: PandocMonad m => ManLexer m ManTokens
-skipConditional = do
-  rest <- anyLine
-  when ("\\{\\" `isSuffixOf` rest) $
-    void $ manyTill anyChar (try (string "\\}"))
-  return mempty
-
-lexIncludeFile :: PandocMonad m => [Arg] -> ManLexer m ManTokens
-lexIncludeFile args = do
-  pos <- getPosition
-  case args of
-    (f:_) -> do
-      let fp = linePartsToString f
-      dirs <- getResourcePath
-      result <- readFileFromDirs dirs fp
-      case result of
-        Nothing  -> report $ CouldNotLoadIncludeFile fp pos
-        Just s   -> getInput >>= setInput . (s ++)
-      return mempty
-    []    -> return mempty
-
-resolveMacro :: PandocMonad m
-             => String -> [Arg] -> SourcePos -> ManLexer m ManTokens
-resolveMacro macroName args pos = do
-  macros <- customMacros <$> getState
-  case M.lookup macroName macros of
-    Nothing -> return $ singleTok $ MMacro macroName args pos
-    Just ts -> do
-      let fillLP (RoffStr (x,y)) zs = RoffStr (x,y) : zs
-          fillLP (MacroArg i)    zs =
-            case drop (i - 1) args of
-              []     -> zs
-              (ys:_) -> ys ++ zs
-      let fillMacroArg (MLine lineparts) =
-            MLine (foldr fillLP [] lineparts)
-          fillMacroArg x = x
-      return $ ManTokens . fmap fillMacroArg . unManTokens $ ts
-
-lexStringDef :: PandocMonad m => [Arg] -> ManLexer m ManTokens
-lexStringDef args = do -- string definition
-   case args of
-     []     -> fail "No argument to .ds"
-     (x:ys) -> do
-       let ts = singleTok $ MLine (intercalate [RoffStr (" ", mempty)] ys)
-       let stringName = linePartsToString x
-       modifyState $ \st ->
-         st{ customMacros = M.insert stringName ts (customMacros st) }
-   return mempty
-
-lexMacroDef :: PandocMonad m => [Arg] -> ManLexer m ManTokens
-lexMacroDef args = do -- macro definition
-   (macroName, stopMacro) <-
-     case args of
-       (x : y : _) -> return (linePartsToString x, linePartsToString y)
-                      -- optional second arg
-       (x:_)       -> return (linePartsToString x, ".")
-       []          -> fail "No argument to .de"
-   let stop = try $ do
-         char '.' <|> char '\''
-         many spacetab
-         string stopMacro
-         _ <- lexArgs
-         return ()
-   ts <- mconcat <$> manyTill manToken stop
-   modifyState $ \st ->
-     st{ customMacros = M.insert macroName ts (customMacros st) }
-   return mempty
-
-lexArgs :: PandocMonad m => ManLexer m [Arg]
-lexArgs = do
-  args <- many $ try oneArg
-  skipMany spacetab
-  eofline
-  return args
-
-  where
-
-  oneArg :: PandocMonad m => ManLexer m [LinePart]
-  oneArg = do
-    skipMany $ try $ string "\\\n"  -- continuation line
-    try quotedArg <|> plainArg
-    -- try, because there are some erroneous files, e.g. linux/bpf.2
-
-  plainArg :: PandocMonad m => ManLexer m [LinePart]
-  plainArg = do
-    skipMany spacetab
-    mconcat <$> many1
-      (macroArg <|> esc <|> regularText <|> unescapedQuote <|> escStar)
-    where
-      unescapedQuote = do
-         char '"'
-         fonts <- currentFont
-         return [RoffStr ("\"", fonts)]
-
-
-  quotedArg :: PandocMonad m => ManLexer m [LinePart]
-  quotedArg = do
-    skipMany spacetab
-    char '"'
-    xs <- mconcat <$>
-           many (macroArg <|> esc <|> escStar <|> regularText
-                 <|> spaceTabChar <|> escapedQuote)
-    char '"'
-    return xs
-    where
-      escapedQuote = try $ do
-        char '"'
-        char '"'
-        fonts <- currentFont
-        return [RoffStr ("\"", fonts)]
-
-escStar :: PandocMonad m => ManLexer m [LinePart]
-escStar = try $ do
-  pos <- getPosition
-  char '\\'
-  char '*'
-  c <- anyChar
-  case c of
-    '(' -> do
-      cs <- count 2 anyChar
-      resolveString cs pos
-    '[' -> do
-      cs <- many (noneOf "\t\n\r ]")
-      char ']'
-      resolveString cs pos
-    'S' -> return mempty -- switch back to default font size
-    _   -> resolveString [c] pos
-
-  where
-
-  -- strings and macros share namespace
-  resolveString stringname pos = do
-    ManTokens ts <- resolveMacro stringname [] pos
-    case Foldable.toList ts of
-      [MLine xs] -> return xs
-      _          -> do
-        report $ SkippedContent ("unknown string " ++ stringname) pos
-        return mempty
-
-lexLine :: PandocMonad m => ManLexer m ManTokens
-lexLine = do
-  lnparts <- mconcat <$> many1 linePart
-  eofline
-  go lnparts
-  where  -- return empty line if we only have empty strings;
-         -- this can happen if the line just contains \f[C], for example.
-    go [] = return mempty
-    go (RoffStr ("",_):xs) = go xs
-    go xs = return $ singleTok $ MLine xs
-
-linePart :: PandocMonad m => ManLexer m [LinePart]
-linePart = macroArg <|> esc <|> escStar <|>
-           regularText <|> quoteChar <|> spaceTabChar
-
-macroArg :: PandocMonad m => ManLexer m [LinePart]
-macroArg = try $ do
-  string "\\\\$"
-  x <- digit
-  return [MacroArg $ ord x - ord '0']
-
-esc :: PandocMonad m => ManLexer m [LinePart]
-esc = do
-  s <- escapeLexer
-  font <- currentFont
-  return [RoffStr (s, font)]
-
-regularText :: PandocMonad m => ManLexer m [LinePart]
-regularText = do
-  s <- many1 $ noneOf "\n\r\t \\\""
-  font <- currentFont
-  return [RoffStr (s, font)]
-
-quoteChar :: PandocMonad m => ManLexer m [LinePart]
-quoteChar = do
-  char '"'
-  font <- currentFont
-  return [RoffStr ("\"", font)]
-
-spaceTabChar :: PandocMonad m => ManLexer m [LinePart]
-spaceTabChar = do
-  c <- spacetab
-  font <- currentFont
-  return [RoffStr ([c], font)]
-
-lexEmptyLine :: PandocMonad m => ManLexer m ManTokens
-lexEmptyLine = char '\n' >> return (singleTok MEmptyLine)
-
-manToken :: PandocMonad m => ManLexer m ManTokens
-manToken = lexComment <|> lexMacro <|> lexLine <|> lexEmptyLine
 
 parseMan :: PandocMonad m => ManParser m Pandoc
 parseMan = do
@@ -656,12 +203,6 @@ linePartsToInlines = go
     isItalic (RoffStr (_,f)) = Italic `S.member` f
     isItalic _ = False
 
-linePartsToString :: [LinePart] -> String
-linePartsToString = mconcat . map go
-  where
-  go (RoffStr (s, _)) = s
-  go _ = mempty
-
 parsePara :: PandocMonad m => ManParser m Blocks
 parsePara = para . trimInlines <$> parseInlines