52a8116 · typeable/pandoc

git.iko.soy/typeable/pandoc

Merge pull request #4153 from tarleb/unify-lua-init

Unify lua initalization

commit52a8116e71636f05053c959675b3abcb745e921a authorJohn MacFarlane <jgm@berkeley.edu> dateWed 13 Dec 2017, 21:42 (9 years ago) parent4405336 4c64af4

6 files changed+184−149

compare with master

unifiedsplit

pandoc.cabal+2−1 src/Text/Pandoc/App.hs+2−2 src/Text/Pandoc/Lua.hs+14−53 src/Text/Pandoc/Lua/Init.hs+79 src/Text/Pandoc/Writers/Custom.hs+69−80 test/Tests/Lua.hs+18−13

pandoc.cabal+2−1

@@ -523,9 +523,10 @@ library

523523 Text.Pandoc.Readers.Org.ParserState,

524524 Text.Pandoc.Readers.Org.Parsing,

525525 Text.Pandoc.Readers.Org.Shared,

526+ Text.Pandoc.Lua.Filter,

527+ Text.Pandoc.Lua.Init,

526528 Text.Pandoc.Lua.Packages,

527529 Text.Pandoc.Lua.PandocModule,

528− Text.Pandoc.Lua.Filter,

529530 Text.Pandoc.Lua.StackInstances,

530531 Text.Pandoc.Lua.Util,

531532 Text.Pandoc.CSS,

src/Text/Pandoc/App.hs+2−2

@@ -223,7 +223,7 @@ convertWithOpts opts = do

223223 if ".lua" `isSuffixOf` format

224224 -- note: use non-lowercased version writerName

225225 then return (TextWriter

226− (\o d -> liftIO $ writeCustom writerName o d)

226+ (\o d -> writeCustom writerName o d)

227227 :: Writer PandocIO, mempty)

228228 else case getWriter writerName of

229229 Left e -> E.throwIO $ PandocAppError $

@@ -846,7 +846,7 @@ applyLuaFilters :: Maybe FilePath -> [FilePath] -> String -> Pandoc

846846applyLuaFilters mbDatadir filters format d = do

847847 expandedFilters <- mapM (expandFilterPath mbDatadir) filters

848848 let go f d' = do

849− res <- runLuaFilter mbDatadir f format d'

849+ res <- runLuaFilter f format d'

850850 case res of

851851 Right x -> return x

852852 Left (LuaException s) -> E.throw (PandocFilterError f s)

src/Text/Pandoc/Lua.hs+14−53

@@ -1,9 +1,3 @@

1−{-# LANGUAGE CPP #-}

2−{-# LANGUAGE FlexibleContexts #-}

3−{-# LANGUAGE FlexibleInstances #-}

4−{-# LANGUAGE MultiParamTypeClasses #-}

5−{-# LANGUAGE ScopedTypeVariables #-}

6−{-# OPTIONS_GHC -fno-warn-orphans #-}

71{-

@@ -29,48 +23,36 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

2923 Maintainer : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>

3024 Stability : alpha

3125

32−Pandoc lua utils.

26+Running pandoc Lua filters.

3327-}

3428module Text.Pandoc.Lua

3529 ( LuaException (..)

36− , LuaPackageParams (..)

37− , pushPandocModule

3830 , runLuaFilter

39− , initLuaState

40− , luaPackageParams

31+ , runPandocLua

32+ , pushPandocModule

4133 ) where

4234

4335import Control.Monad (when, (>=>))

44−import Control.Monad.Identity (Identity)

45−import Control.Monad.Trans (MonadIO (..))

46−import Data.IORef (newIORef, readIORef)

4736import Foreign.Lua (FromLuaStack (peek), Lua, LuaException (..),

4837 Status (OK), ToLuaStack (push))

49−import Text.Pandoc.Class (PandocIO, getCommonState, getMediaBag, setMediaBag)

50−import Text.Pandoc.Definition

38+import Text.Pandoc.Class (PandocIO)

39+import Text.Pandoc.Definition (Pandoc)

5140import Text.Pandoc.Lua.Filter (LuaFilter, walkMWithLuaFilter)

52−import Text.Pandoc.Lua.Packages (LuaPackageParams (..),

53− installPandocPackageSearcher)

41+import Text.Pandoc.Lua.Init (runPandocLua)

5442import Text.Pandoc.Lua.PandocModule (pushPandocModule) -- TODO: remove

55−import Text.Pandoc.Lua.Util (loadScriptFromDataDir)

5643import qualified Foreign.Lua as Lua

57−import qualified Foreign.Lua.Module.Text as Lua

5844

59−runLuaFilter :: Maybe FilePath -> FilePath -> String

45+-- | Run the Lua filter in @filterPath@ for a transformation to target

46+-- format @format@. Pandoc uses Lua init files to setup the Lua

47+-- interpreter.

48+runLuaFilter :: FilePath -> String

6049 -> Pandoc -> PandocIO (Either LuaException Pandoc)

61−runLuaFilter datadir filterPath format pd = do

62− luaPkgParams <- luaPackageParams datadir

63− res <- liftIO . Lua.runLuaEither $

64− runLuaFilter' luaPkgParams filterPath format pd

65− newMediaBag <- liftIO (readIORef (luaPkgMediaBag luaPkgParams))

66− setMediaBag newMediaBag

67− return res

50+runLuaFilter filterPath format doc =

51+ runPandocLua (runLuaFilter' filterPath format doc)

6852

69−runLuaFilter' :: LuaPackageParams

70− -> FilePath -> String

53+runLuaFilter' :: FilePath -> String

7154 -> Pandoc -> Lua Pandoc

72−runLuaFilter' luaPkgOpts filterPath format pd = do

73− initLuaState luaPkgOpts

55+runLuaFilter' filterPath format pd = do

7456 -- store module in global "pandoc"

7557 registerFormat

7658 top <- Lua.gettop

@@ -90,24 +72,6 @@ runLuaFilter' luaPkgOpts filterPath format pd = do

9072 push format

9173 Lua.setglobal "FORMAT"

9274

93−luaPackageParams :: Maybe FilePath -> PandocIO LuaPackageParams

94−luaPackageParams datadir = do

95− commonState <- getCommonState

96− mbRef <- liftIO . newIORef =<< getMediaBag

97− return LuaPackageParams

98− { luaPkgCommonState = commonState

99− , luaPkgDataDir = datadir

100− , luaPkgMediaBag = mbRef

101− }

102−

103−-- Initialize the lua state with all required values

104−initLuaState :: LuaPackageParams -> Lua ()

105−initLuaState luaPkgParams = do

106− Lua.openlibs

107− Lua.preloadTextModule "text"

108− installPandocPackageSearcher luaPkgParams

109− loadScriptFromDataDir (luaPkgDataDir luaPkgParams) "init.lua"

110−

11175pushGlobalFilter :: Lua ()

11276pushGlobalFilter = do

11377 Lua.newtable

@@ -117,6 +81,3 @@ pushGlobalFilter = do

11781

11882runAll :: [LuaFilter] -> Pandoc -> Lua Pandoc

11983runAll = foldr ((>=>) . walkMWithLuaFilter) return

120−

121−instance (FromLuaStack a) => FromLuaStack (Identity a) where

122− peek = fmap return . peek

src/Text/Pandoc/Lua/Init.hsnew file+79

@@ -0,0 +1,79 @@

1+{-

4+This program is free software; you can redistribute it and/or modify

5+it under the terms of the GNU General Public License as published by

6+the Free Software Foundation; either version 2 of the License, or

7+(at your option) any later version.

9+This program is distributed in the hope that it will be useful,

10+but WITHOUT ANY WARRANTY; without even the implied warranty of

11+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

12+GNU General Public License for more details.

13+

14+You should have received a copy of the GNU General Public License

15+along with this program; if not, write to the Free Software

16+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

17+-}

18+{- |

19+ Module : Text.Pandoc.Lua

21+ License : GNU GPL, version 2 or above

22+

23+ Maintainer : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>

24+ Stability : alpha

25+

26+Functions to initialize the Lua interpreter.

27+-}

28+module Text.Pandoc.Lua.Init

29+ ( LuaException (..)

30+ , LuaPackageParams (..)

31+ , runPandocLua

32+ , initLuaState

33+ , luaPackageParams

34+ ) where

35+

36+import Control.Monad.Trans (MonadIO (..))

37+import Data.IORef (newIORef, readIORef)

38+import Foreign.Lua (Lua, LuaException (..))

39+import GHC.IO.Encoding (getForeignEncoding, setForeignEncoding, utf8)

40+import Text.Pandoc.Class (PandocIO, getCommonState, getUserDataDir, getMediaBag,

41+ setMediaBag)

42+import Text.Pandoc.Lua.Packages (LuaPackageParams (..),

43+ installPandocPackageSearcher)

44+import Text.Pandoc.Lua.Util (loadScriptFromDataDir)

45+

46+import qualified Foreign.Lua as Lua

47+import qualified Foreign.Lua.Module.Text as Lua

48+

49+-- | Run the lua interpreter, using pandoc's default way of environment

50+-- initalization.

51+runPandocLua :: Lua a -> PandocIO (Either LuaException a)

52+runPandocLua luaOp = do

53+ datadir <- getUserDataDir

54+ luaPkgParams <- luaPackageParams datadir

55+ enc <- liftIO $ getForeignEncoding <* setForeignEncoding utf8

56+ res <- liftIO $ Lua.runLuaEither (initLuaState luaPkgParams *> luaOp)

57+ liftIO $ setForeignEncoding enc

58+ newMediaBag <- liftIO (readIORef (luaPkgMediaBag luaPkgParams))

59+ setMediaBag newMediaBag

60+ return res

61+

62+-- | Generate parameters required to setup pandoc's lua environment.

63+luaPackageParams :: Maybe FilePath -> PandocIO LuaPackageParams

64+luaPackageParams datadir = do

65+ commonState <- getCommonState

66+ mbRef <- liftIO . newIORef =<< getMediaBag

67+ return LuaPackageParams

68+ { luaPkgCommonState = commonState

69+ , luaPkgDataDir = datadir

70+ , luaPkgMediaBag = mbRef

71+ }

72+

73+-- Initialize the lua state with all required values

74+initLuaState :: LuaPackageParams -> Lua ()

75+initLuaState luaPkgParams = do

76+ Lua.openlibs

77+ Lua.preloadTextModule "text"

78+ installPandocPackageSearcher luaPkgParams

79+ loadScriptFromDataDir (luaPkgDataDir luaPkgParams) "init.lua"

src/Text/Pandoc/Writers/Custom.hs+69−80

@@ -1,11 +1,5 @@

1−{-# OPTIONS_GHC -fno-warn-orphans #-}

2−{-# LANGUAGE CPP #-}

31{-# LANGUAGE DeriveDataTypeable #-}

42{-# LANGUAGE FlexibleInstances #-}

5−#if MIN_VERSION_base(4,8,0)

6−#else

7−{-# LANGUAGE OverlappingInstances #-}

8−#endif

104

115This program is free software; you can redistribute it and/or modify

@@ -36,19 +30,23 @@ Conversion of 'Pandoc' documents to custom markup using

3630a lua writer.

3731-}

3832module Text.Pandoc.Writers.Custom ( writeCustom ) where

33+import Control.Arrow ((***))

3934import Control.Exception

4035import Control.Monad (when)

36+import Control.Monad.Trans (MonadIO (liftIO))

4137import Data.Char (toLower)

4238import Data.List (intersperse)

4339import qualified Data.Map as M

4440import Data.Text (Text, pack)

4541import Data.Typeable

46−import Foreign.Lua (Lua, ToLuaStack (..), callFunc, runLua)

42+import Foreign.Lua (Lua, ToLuaStack (..), callFunc)

4743import Foreign.Lua.Api

48−import GHC.IO.Encoding (getForeignEncoding, setForeignEncoding, utf8)

44+import Text.Pandoc.Class (PandocIO)

4945import Text.Pandoc.Definition

5046import Text.Pandoc.Error

51−import Text.Pandoc.Lua.Util (addValue)

47+import Text.Pandoc.Lua.Init (runPandocLua)

48+import Text.Pandoc.Lua.StackInstances ()

49+import Text.Pandoc.Lua.Util (addValue, dostring')

5250import Text.Pandoc.Options

5351import Text.Pandoc.Templates

5452import qualified Text.Pandoc.UTF8 as UTF8

@@ -60,43 +58,31 @@ attrToMap (id',classes,keyvals) = M.fromList

6058 : ("class", unwords classes)

6159 : keyvals

6260

63−instance ToLuaStack Double where

64− push = push . (realToFrac :: Double -> LuaNumber)

65−

66−instance ToLuaStack Int where

67− push = push . (fromIntegral :: Int -> LuaInteger)

68−

69−instance ToLuaStack Format where

70− push (Format f) = push (map toLower f)

71−

72−#if MIN_VERSION_base(4,8,0)

73−instance {-# OVERLAPS #-} ToLuaStack [Inline] where

74−#else

75−instance ToLuaStack [Inline] where

76−#endif

77− push ils = push =<< inlineListToCustom ils

78−

79−#if MIN_VERSION_base(4,8,0)

80−instance {-# OVERLAPS #-} ToLuaStack [Block] where

81−#else

82−instance ToLuaStack [Block] where

83−#endif

84− push ils = push =<< blockListToCustom ils

85−

86−instance ToLuaStack MetaValue where

87− push (MetaMap m) = push m

88− push (MetaList xs) = push xs

89− push (MetaBool x) = push x

90− push (MetaString s) = push s

91− push (MetaInlines ils) = push ils

92− push (MetaBlocks bs) = push bs

93−

94−instance ToLuaStack Citation where

95− push cit = do

61+newtype Stringify a = Stringify a

62+

63+instance ToLuaStack (Stringify Format) where

64+ push (Stringify (Format f)) = push (map toLower f)

65+

66+instance ToLuaStack (Stringify [Inline]) where

67+ push (Stringify ils) = push =<< inlineListToCustom ils

68+

69+instance ToLuaStack (Stringify [Block]) where

70+ push (Stringify blks) = push =<< blockListToCustom blks

71+

72+instance ToLuaStack (Stringify MetaValue) where

73+ push (Stringify (MetaMap m)) = push (fmap Stringify m)

74+ push (Stringify (MetaList xs)) = push (map Stringify xs)

75+ push (Stringify (MetaBool x)) = push x

76+ push (Stringify (MetaString s)) = push s

77+ push (Stringify (MetaInlines ils)) = push (Stringify ils)

78+ push (Stringify (MetaBlocks bs)) = push (Stringify bs)

79+

80+instance ToLuaStack (Stringify Citation) where

81+ push (Stringify cit) = do

9682 createtable 6 0

9783 addValue "citationId" $ citationId cit

98− addValue "citationPrefix" $ citationPrefix cit

99− addValue "citationSuffix" $ citationSuffix cit

84+ addValue "citationPrefix" . Stringify $ citationPrefix cit

85+ addValue "citationSuffix" . Stringify $ citationSuffix cit

10086 addValue "citationMode" $ show (citationMode cit)

10187 addValue "citationNoteNum" $ citationNoteNum cit

10288 addValue "citationHash" $ citationHash cit

@@ -107,14 +93,11 @@ data PandocLuaException = PandocLuaException String

10793instance Exception PandocLuaException

10894

10995-- | Convert Pandoc to custom markup.

110−writeCustom :: FilePath -> WriterOptions -> Pandoc -> IO Text

96+writeCustom :: FilePath -> WriterOptions -> Pandoc -> PandocIO Text

11197writeCustom luaFile opts doc@(Pandoc meta _) = do

112− luaScript <- UTF8.readFile luaFile

113− enc <- getForeignEncoding

114− setForeignEncoding utf8

115− (body, context) <- runLua $ do

116− openlibs

117− stat <- loadstring luaScript

98+ luaScript <- liftIO $ UTF8.readFile luaFile

99+ res <- runPandocLua $ do

100+ stat <- dostring' luaScript

118101 -- check for error in lua script (later we'll change the return type

119102 -- to handle this more gracefully):

120103 when (stat /= OK) $

@@ -127,7 +110,9 @@ writeCustom luaFile opts doc@(Pandoc meta _) = do

127110 inlineListToCustom

128111 meta

129112 return (rendered, context)

130− setForeignEncoding enc

113+ let (body, context) = case res of

114+ Left e -> throw (PandocLuaException (show e))

115+ Right x -> x

131116 case writerTemplate opts of

132117 Nothing -> return $ pack body

133118 Just tpl ->

@@ -138,7 +123,7 @@ writeCustom luaFile opts doc@(Pandoc meta _) = do

138123docToCustom :: WriterOptions -> Pandoc -> Lua String

139124docToCustom opts (Pandoc (Meta metamap) blocks) = do

140125 body <- blockListToCustom blocks

141− callFunc "Doc" body metamap (writerVariables opts)

126+ callFunc "Doc" body (fmap Stringify metamap) (writerVariables opts)

142127

143128-- | Convert Pandoc block element to Custom.

144129blockToCustom :: Block -- ^ Block element

@@ -146,41 +131,45 @@ blockToCustom :: Block -- ^ Block element

146131

147132blockToCustom Null = return ""

148133

149−blockToCustom (Plain inlines) = callFunc "Plain" inlines

134+blockToCustom (Plain inlines) = callFunc "Plain" (Stringify inlines)

150135

151136blockToCustom (Para [Image attr txt (src,tit)]) =

152− callFunc "CaptionedImage" src tit txt (attrToMap attr)

137+ callFunc "CaptionedImage" src tit (Stringify txt) (attrToMap attr)

153138

154−blockToCustom (Para inlines) = callFunc "Para" inlines

139+blockToCustom (Para inlines) = callFunc "Para" (Stringify inlines)

155140

156−blockToCustom (LineBlock linesList) = callFunc "LineBlock" linesList

141+blockToCustom (LineBlock linesList) = callFunc "LineBlock" (map Stringify linesList)

157142

158143blockToCustom (RawBlock format str) =

159− callFunc "RawBlock" format str

144+ callFunc "RawBlock" (Stringify format) str

160145

161146blockToCustom HorizontalRule = callFunc "HorizontalRule"

162147

163148blockToCustom (Header level attr inlines) =

164− callFunc "Header" level inlines (attrToMap attr)

149+ callFunc "Header" level (Stringify inlines) (attrToMap attr)

165150

166151blockToCustom (CodeBlock attr str) =

167152 callFunc "CodeBlock" str (attrToMap attr)

168153

169−blockToCustom (BlockQuote blocks) = callFunc "BlockQuote" blocks

154+blockToCustom (BlockQuote blocks) = callFunc "BlockQuote" (Stringify blocks)

170155

171−blockToCustom (Table capt aligns widths headers rows') =

172− callFunc "Table" capt (map show aligns) widths headers rows'

156+blockToCustom (Table capt aligns widths headers rows) =

157+ let aligns' = map show aligns

158+ capt' = Stringify capt

159+ headers' = map Stringify headers

160+ rows' = map (map Stringify) rows

161+ in callFunc "Table" capt' aligns' widths headers' rows'

173162

174−blockToCustom (BulletList items) = callFunc "BulletList" items

163+blockToCustom (BulletList items) = callFunc "BulletList" (map Stringify items)

175164

176165blockToCustom (OrderedList (num,sty,delim) items) =

177− callFunc "OrderedList" items num (show sty) (show delim)

166+ callFunc "OrderedList" (map Stringify items) num (show sty) (show delim)

178167

179168blockToCustom (DefinitionList items) =

180− callFunc "DefinitionList" items

169+ callFunc "DefinitionList" (map (Stringify *** map Stringify) items)

181170

182171blockToCustom (Div attr items) =

183− callFunc "Div" items (attrToMap attr)

172+ callFunc "Div" (Stringify items) (attrToMap attr)

184173

185174-- | Convert list of Pandoc block elements to Custom.

186175blockListToCustom :: [Block] -- ^ List of block elements

@@ -205,23 +194,23 @@ inlineToCustom Space = callFunc "Space"

205194

206195inlineToCustom SoftBreak = callFunc "SoftBreak"

207196

208−inlineToCustom (Emph lst) = callFunc "Emph" lst

197+inlineToCustom (Emph lst) = callFunc "Emph" (Stringify lst)

209198

210−inlineToCustom (Strong lst) = callFunc "Strong" lst

199+inlineToCustom (Strong lst) = callFunc "Strong" (Stringify lst)

211200

212−inlineToCustom (Strikeout lst) = callFunc "Strikeout" lst

201+inlineToCustom (Strikeout lst) = callFunc "Strikeout" (Stringify lst)

213202

214−inlineToCustom (Superscript lst) = callFunc "Superscript" lst

203+inlineToCustom (Superscript lst) = callFunc "Superscript" (Stringify lst)

215204

216−inlineToCustom (Subscript lst) = callFunc "Subscript" lst

205+inlineToCustom (Subscript lst) = callFunc "Subscript" (Stringify lst)

217206

218−inlineToCustom (SmallCaps lst) = callFunc "SmallCaps" lst

207+inlineToCustom (SmallCaps lst) = callFunc "SmallCaps" (Stringify lst)

219208

220−inlineToCustom (Quoted SingleQuote lst) = callFunc "SingleQuoted" lst

209+inlineToCustom (Quoted SingleQuote lst) = callFunc "SingleQuoted" (Stringify lst)

221210

222−inlineToCustom (Quoted DoubleQuote lst) = callFunc "DoubleQuoted" lst

211+inlineToCustom (Quoted DoubleQuote lst) = callFunc "DoubleQuoted" (Stringify lst)

223212

224−inlineToCustom (Cite cs lst) = callFunc "Cite" lst cs

213+inlineToCustom (Cite cs lst) = callFunc "Cite" (Stringify lst) (map Stringify cs)

225214

226215inlineToCustom (Code attr str) =

227216 callFunc "Code" str (attrToMap attr)

@@ -233,17 +222,17 @@ inlineToCustom (Math InlineMath str) =

233222 callFunc "InlineMath" str

234223

235224inlineToCustom (RawInline format str) =

236− callFunc "RawInline" format str

225+ callFunc "RawInline" (Stringify format) str

237226

238227inlineToCustom LineBreak = callFunc "LineBreak"

239228

240229inlineToCustom (Link attr txt (src,tit)) =

241− callFunc "Link" txt src tit (attrToMap attr)

230+ callFunc "Link" (Stringify txt) src tit (attrToMap attr)

242231

243232inlineToCustom (Image attr alt (src,tit)) =

244− callFunc "Image" alt src tit (attrToMap attr)

233+ callFunc "Image" (Stringify alt) src tit (attrToMap attr)

245234

246−inlineToCustom (Note contents) = callFunc "Note" contents

235+inlineToCustom (Note contents) = callFunc "Note" (Stringify contents)

247236

248237inlineToCustom (Span attr items) =

249− callFunc "Span" items (attrToMap attr)

238+ callFunc "Span" (Stringify items) (attrToMap attr)

test/Tests/Lua.hs+18−13

@@ -10,9 +10,9 @@ import Text.Pandoc.Arbitrary ()

1010import Text.Pandoc.Builder (bulletList, divWith, doc, doubleQuoted, emph,

1111 header, linebreak, para, plain, rawBlock,

1212 singleQuoted, space, str, strong, (<>))

13−import Text.Pandoc.Class (runIOorExplode)

13+import Text.Pandoc.Class (runIOorExplode, setUserDataDir)

1414import Text.Pandoc.Definition (Block, Inline, Meta, Pandoc)

15−import Text.Pandoc.Lua (initLuaState, runLuaFilter, luaPackageParams)

15+import Text.Pandoc.Lua (runLuaFilter, runPandocLua)

1616

1717import qualified Foreign.Lua as Lua

1818

@@ -95,8 +95,9 @@ tests = map (localOption (QuickCheckTests 20))

9595

9696assertFilterConversion :: String -> FilePath -> Pandoc -> Pandoc -> Assertion

9797assertFilterConversion msg filterPath docIn docExpected = do

98− docEither <- runIOorExplode $

99− runLuaFilter (Just "../data") ("lua" </> filterPath) [] docIn

98+ docEither <- runIOorExplode $ do

99+ setUserDataDir (Just "../data")

100+ runLuaFilter ("lua" </> filterPath) [] docIn

100101 case docEither of

101102 Left _ -> fail "lua filter failed"

102103 Right docRes -> assertEqual msg docExpected docRes

@@ -105,14 +106,18 @@ roundtripEqual :: (Eq a, Lua.FromLuaStack a, Lua.ToLuaStack a) => a -> IO Bool

105106roundtripEqual x = (x ==) <$> roundtripped

106107 where

107108 roundtripped :: (Lua.FromLuaStack a, Lua.ToLuaStack a) => IO a

108− roundtripped = Lua.runLua $ do

109− initLuaState =<< Lua.liftIO (runIOorExplode (luaPackageParams (Just "../data")))

110− oldSize <- Lua.gettop

111− Lua.push x

112− size <- Lua.gettop

113− when (size - oldSize /= 1) $

114− error ("not exactly one additional element on the stack: " ++ show size)

115− res <- Lua.peekEither (-1)

109+ roundtripped = runIOorExplode $ do

110+ setUserDataDir (Just "../data")

111+ res <- runPandocLua $ do

112+ oldSize <- Lua.gettop

113+ Lua.push x

114+ size <- Lua.gettop

115+ when (size - oldSize /= 1) $

116+ error ("not exactly one additional element on the stack: " ++ show size)

117+ res <- Lua.peekEither (-1)

118+ case res of

119+ Left _ -> error "could not read from stack"

120+ Right y -> return y

116121 case res of

117− Left _ -> error "could not read from stack"

122+ Left e -> error (show e)

118123 Right y -> return y