T.P.Lua: split StackInstances into smaller Marshaling modules

12 files changed, 240 insertions, 175 deletions

diff --git a/pandoc.cabal b/pandoc.cabal
index 55821d8ed..a985b92fe 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -575,11 +575,15 @@ library
                    Text.Pandoc.Lua.Filter,
                    Text.Pandoc.Lua.Global,
                    Text.Pandoc.Lua.Init,
+                   Text.Pandoc.Lua.Marshaling,
+                   Text.Pandoc.Lua.Marshaling.AST,
+                   Text.Pandoc.Lua.Marshaling.AnyValue,
+                   Text.Pandoc.Lua.Marshaling.CommonState,
+                   Text.Pandoc.Lua.Marshaling.ReaderOptions,
                    Text.Pandoc.Lua.Module.MediaBag,
                    Text.Pandoc.Lua.Module.Pandoc,
                    Text.Pandoc.Lua.Module.Utils,
                    Text.Pandoc.Lua.Packages,
-                   Text.Pandoc.Lua.StackInstances,
                    Text.Pandoc.Lua.Util,
                    Text.Pandoc.CSS,
                    Text.Pandoc.CSV,
diff --git a/src/Text/Pandoc/Lua.hs b/src/Text/Pandoc/Lua.hs
index f7338b776..62278b5d2 100644
--- a/src/Text/Pandoc/Lua.hs
+++ b/src/Text/Pandoc/Lua.hs
@@ -39,5 +39,5 @@ module Text.Pandoc.Lua
 import Text.Pandoc.Lua.Filter (runFilterFile)
 import Text.Pandoc.Lua.Global (Global (..), setGlobals)
 import Text.Pandoc.Lua.Init (LuaException (..), runLua)
-import Text.Pandoc.Lua.StackInstances ()
+import Text.Pandoc.Lua.Marshaling ()
 
diff --git a/src/Text/Pandoc/Lua/Filter.hs b/src/Text/Pandoc/Lua/Filter.hs
index cfd50876a..b2aeade74 100644
--- a/src/Text/Pandoc/Lua/Filter.hs
+++ b/src/Text/Pandoc/Lua/Filter.hs
@@ -48,7 +48,7 @@ import Data.Foldable (foldrM)
 import Data.Map (Map)
 import Foreign.Lua (Lua, Peekable, Pushable)
 import Text.Pandoc.Definition
-import Text.Pandoc.Lua.StackInstances ()
+import Text.Pandoc.Lua.Marshaling ()
 import Text.Pandoc.Walk (walkM, Walkable)
 
 import qualified Data.Map.Strict as Map
diff --git a/src/Text/Pandoc/Lua/Global.hs b/src/Text/Pandoc/Lua/Global.hs
index 445ce9e04..b7e8884f4 100644
--- a/src/Text/Pandoc/Lua/Global.hs
+++ b/src/Text/Pandoc/Lua/Global.hs
@@ -41,7 +41,7 @@ import Foreign.Lua.Userdata ( ensureUserdataMetatable, pushAnyWithMetatable
 import Paths_pandoc (version)
 import Text.Pandoc.Class (CommonState)
 import Text.Pandoc.Definition (Pandoc (Pandoc), pandocTypesVersion)
-import Text.Pandoc.Lua.StackInstances ()
+import Text.Pandoc.Lua.Marshaling ()
 import Text.Pandoc.Lua.Util (addFunction)
 import Text.Pandoc.Options (ReaderOptions)
 
diff --git a/src/Text/Pandoc/Lua/Marshaling.hs b/src/Text/Pandoc/Lua/Marshaling.hs
new file mode 100644
index 000000000..cc0451c09
--- /dev/null
+++ b/src/Text/Pandoc/Lua/Marshaling.hs
@@ -0,0 +1,16 @@
+{- |
+   Module      : Text.Pandoc.Lua.Marshaling
+   Copyright   : © 2012-2019 John MacFarlane
+                 © 2017-2019 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+Lua marshaling (pushing) and unmarshaling (peeking) instances.
+-}
+module Text.Pandoc.Lua.Marshaling () where
+
+import Text.Pandoc.Lua.Marshaling.AST ()
+import Text.Pandoc.Lua.Marshaling.CommonState ()
+import Text.Pandoc.Lua.Marshaling.ReaderOptions ()
diff --git a/src/Text/Pandoc/Lua/StackInstances.hs b/src/Text/Pandoc/Lua/Marshaling/AST.hs
index cf75885af..f18754ac2 100644
--- a/src/Text/Pandoc/Lua/StackInstances.hs
+++ b/src/Text/Pandoc/Lua/Marshaling/AST.hs
@@ -1,28 +1,10 @@
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 {-# LANGUAGE NoImplicitPrelude    #-}
 {-# LANGUAGE FlexibleInstances    #-}
 {-# LANGUAGE ScopedTypeVariables  #-}
 {-# LANGUAGE LambdaCase           #-}
-{-# OPTIONS_GHC -fno-warn-orphans #-}
-{-
-Copyright © 2012-2019 John MacFarlane <jgm@berkeley.edu>
-            2017-2019 Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
-
-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.Lua.StackInstances
+   Module      : Text.Pandoc.Lua.Marshaling.AST
    Copyright   : © 2012-2019 John MacFarlane
                  © 2017-2019 Albert Krewinkel
    License     : GNU GPL, version 2 or above
@@ -30,27 +12,20 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
    Stability   : alpha
 
-StackValue instances for pandoc types.
+Marshaling/unmarshaling instances for document AST elements.
 -}
-module Text.Pandoc.Lua.StackInstances () where
+module Text.Pandoc.Lua.Marshaling.AST () where
 
 import Prelude
 import Control.Applicative ((<|>))
-import Data.Data (showConstr, toConstr)
 import Foreign.Lua (Lua, Peekable, Pushable, StackIndex)
-import Foreign.Lua.Types.Peekable (reportValueOnFailure)
 import Foreign.Lua.Userdata ( ensureUserdataMetatable, pushAnyWithMetatable
-                            , toAnyWithName, metatableName)
-import Text.Pandoc.Class (CommonState (..))
+                            , metatableName)
 import Text.Pandoc.Definition
-import Text.Pandoc.Extensions (Extensions)
-import Text.Pandoc.Logging (LogMessage, showLogMessage)
 import Text.Pandoc.Lua.Util (defineHowTo, pushViaConstructor)
-import Text.Pandoc.Options (ReaderOptions (..), TrackChanges)
+import Text.Pandoc.Lua.Marshaling.CommonState ()
 import Text.Pandoc.Shared (Element (Blk, Sec))
 
-import qualified Data.Map as Map
-import qualified Data.Set as Set
 import qualified Foreign.Lua as Lua
 import qualified Text.Pandoc.Lua.Util as LuaUtil
 
@@ -335,140 +310,3 @@ indexElement = \case
     "tag"       -> Lua.push "Sec"
     "t"         -> Lua.push "Sec"
     _           -> Lua.pushnil
-
-
---
--- Reader Options
---
-instance Pushable Extensions where
-  push exts = Lua.push (show exts)
-
-instance Pushable TrackChanges where
-  push = Lua.push . showConstr . toConstr
-
-instance Pushable ReaderOptions where
-  push ro = do
-    let ReaderOptions
-          (extensions            :: Extensions)
-          (standalone            :: Bool)
-          (columns               :: Int)
-          (tabStop               :: Int)
-          (indentedCodeClasses   :: [String])
-          (abbreviations         :: Set.Set String)
-          (defaultImageExtension :: String)
-          (trackChanges          :: TrackChanges)
-          (stripComments         :: Bool)
-          = ro
-    Lua.newtable
-    LuaUtil.addField "extensions" extensions
-    LuaUtil.addField "standalone" standalone
-    LuaUtil.addField "columns" columns
-    LuaUtil.addField "tab_stop" tabStop
-    LuaUtil.addField "indented_code_classes" indentedCodeClasses
-    LuaUtil.addField "abbreviations" abbreviations
-    LuaUtil.addField "default_image_extension" defaultImageExtension
-    LuaUtil.addField "track_changes" trackChanges
-    LuaUtil.addField "strip_comments" stripComments
-
-    -- add metatable
-    let indexReaderOptions :: AnyValue -> AnyValue -> Lua Lua.NumResults
-        indexReaderOptions _tbl (AnyValue key) = do
-          Lua.ltype key >>= \case
-            Lua.TypeString -> Lua.peek key >>= \case
-              "defaultImageExtension" -> Lua.push defaultImageExtension
-              "indentedCodeClasses" -> Lua.push indentedCodeClasses
-              "stripComments" -> Lua.push stripComments
-              "tabStop" -> Lua.push tabStop
-              "trackChanges" -> Lua.push trackChanges
-              _ -> Lua.pushnil
-            _ -> Lua.pushnil
-          return 1
-    Lua.newtable
-    LuaUtil.addFunction "__index" indexReaderOptions
-    Lua.setmetatable (Lua.nthFromTop 2)
-
--- | Dummy type to allow values of arbitrary Lua type.
-newtype AnyValue = AnyValue StackIndex
-
---
--- TODO: Much of the following should be abstracted, factored out
--- and go into HsLua.
---
-
-instance Peekable AnyValue where
-  peek = return . AnyValue
-
--- | Name used by Lua for the @CommonState@ type.
-commonStateTypeName :: String
-commonStateTypeName = "Pandoc CommonState"
-
-instance Peekable CommonState where
-  peek idx = reportValueOnFailure commonStateTypeName
-             (`toAnyWithName` commonStateTypeName) idx
-
-instance Pushable CommonState where
-  push st = pushAnyWithMetatable pushCommonStateMetatable st
-   where
-    pushCommonStateMetatable = ensureUserdataMetatable commonStateTypeName $ do
-      LuaUtil.addFunction "__index" indexCommonState
-      LuaUtil.addFunction "__pairs" pairsCommonState
-
-indexCommonState :: CommonState -> AnyValue -> Lua Lua.NumResults
-indexCommonState st (AnyValue idx) = Lua.ltype idx >>= \case
-  Lua.TypeString -> 1 <$ (Lua.peek idx >>= pushField)
-  _ -> 1 <$ Lua.pushnil
- where
-  pushField :: String -> Lua ()
-  pushField name = case lookup name commonStateFields of
-    Just pushValue -> pushValue st
-    Nothing -> Lua.pushnil
-
-pairsCommonState :: CommonState -> Lua Lua.NumResults
-pairsCommonState st = do
-  Lua.pushHaskellFunction nextFn
-  Lua.pushnil
-  Lua.pushnil
-  return 3
- where
-  nextFn :: AnyValue -> AnyValue -> Lua Lua.NumResults
-  nextFn _ (AnyValue idx) =
-    Lua.ltype idx >>= \case
-      Lua.TypeNil -> case commonStateFields of
-        []  -> 2 <$ (Lua.pushnil *> Lua.pushnil)
-        (key, pushValue):_ -> 2 <$ (Lua.push key *> pushValue st)
-      Lua.TypeString -> do
-        key <- Lua.peek idx
-        case tail $ dropWhile ((/= key) . fst) commonStateFields of
-          []                     -> 2 <$ (Lua.pushnil *> Lua.pushnil)
-          (nextKey, pushValue):_ -> 2 <$ (Lua.push nextKey *> pushValue st)
-      _ -> 2 <$ (Lua.pushnil *> Lua.pushnil)
-
-commonStateFields :: [(String, CommonState -> Lua ())]
-commonStateFields =
-  [ ("input_files", Lua.push . stInputFiles)
-  , ("output_file", Lua.push . Lua.Optional . stOutputFile)
-  , ("log", Lua.push . stLog)
-  , ("request_headers", Lua.push . Map.fromList . stRequestHeaders)
-  , ("resource_path", Lua.push . stResourcePath)
-  , ("source_url", Lua.push . Lua.Optional . stSourceURL)
-  , ("user_data_dir", Lua.push . Lua.Optional . stUserDataDir)
-  , ("trace", Lua.push . stTrace)
-  , ("verbosity", Lua.push . show . stVerbosity)
-  ]
-
--- | Name used by Lua for the @CommonState@ type.
-logMessageTypeName :: String
-logMessageTypeName = "Pandoc LogMessage"
-
-instance Peekable LogMessage where
-  peek idx = reportValueOnFailure logMessageTypeName
-             (`toAnyWithName` logMessageTypeName) idx
-
-instance Pushable LogMessage where
-  push msg = pushAnyWithMetatable pushLogMessageMetatable msg
-   where
-    pushLogMessageMetatable = ensureUserdataMetatable logMessageTypeName $
-      LuaUtil.addFunction "__tostring" tostringLogMessage
-
-tostringLogMessage :: LogMessage -> Lua String
-tostringLogMessage = return . showLogMessage
diff --git a/src/Text/Pandoc/Lua/Marshaling/AnyValue.hs b/src/Text/Pandoc/Lua/Marshaling/AnyValue.hs
new file mode 100644
index 000000000..a5ff3f2ba
--- /dev/null
+++ b/src/Text/Pandoc/Lua/Marshaling/AnyValue.hs
@@ -0,0 +1,26 @@
+{-# LANGUAGE NoImplicitPrelude    #-}
+{- |
+   Module      : Text.Pandoc.Lua.Marshaling.AnyValue
+   Copyright   : © 2017-2019 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+Helper type to work with raw Lua stack indices instead of unmarshaled
+values.
+
+TODO: Most of this module should be abstracted, factored out, and go
+into HsLua.
+-}
+module Text.Pandoc.Lua.Marshaling.AnyValue (AnyValue (..)) where
+
+import Prelude
+import Foreign.Lua (Peekable (peek), StackIndex)
+
+-- | Dummy type to allow values of arbitrary Lua type. This just wraps
+-- stack indices, using it requires extra care.
+newtype AnyValue = AnyValue StackIndex
+
+instance Peekable AnyValue where
+  peek = return . AnyValue
diff --git a/src/Text/Pandoc/Lua/Marshaling/CommonState.hs b/src/Text/Pandoc/Lua/Marshaling/CommonState.hs
new file mode 100644
index 000000000..eed1500ec
--- /dev/null
+++ b/src/Text/Pandoc/Lua/Marshaling/CommonState.hs
@@ -0,0 +1,102 @@
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+{-# LANGUAGE LambdaCase           #-}
+{-# LANGUAGE NoImplicitPrelude    #-}
+{- |
+   Module      : Text.Pandoc.Lua.Marshaling.CommonState
+   Copyright   : © 2012-2019 John MacFarlane
+                 © 2017-2019 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+Instances to marshal (push) and unmarshal (peek) the common state.
+-}
+module Text.Pandoc.Lua.Marshaling.CommonState () where
+
+import Prelude
+import Foreign.Lua (Lua, Peekable, Pushable)
+import Foreign.Lua.Types.Peekable (reportValueOnFailure)
+import Foreign.Lua.Userdata (ensureUserdataMetatable, pushAnyWithMetatable,
+                             toAnyWithName)
+import Text.Pandoc.Class (CommonState (..))
+import Text.Pandoc.Logging (LogMessage, showLogMessage)
+import Text.Pandoc.Lua.Marshaling.AnyValue (AnyValue (..))
+
+import qualified Data.Map as Map
+import qualified Foreign.Lua as Lua
+import qualified Text.Pandoc.Lua.Util as LuaUtil
+
+-- | Name used by Lua for the @CommonState@ type.
+commonStateTypeName :: String
+commonStateTypeName = "Pandoc CommonState"
+
+instance Peekable CommonState where
+  peek idx = reportValueOnFailure commonStateTypeName
+             (`toAnyWithName` commonStateTypeName) idx
+
+instance Pushable CommonState where
+  push st = pushAnyWithMetatable pushCommonStateMetatable st
+   where
+    pushCommonStateMetatable = ensureUserdataMetatable commonStateTypeName $ do
+      LuaUtil.addFunction "__index" indexCommonState
+      LuaUtil.addFunction "__pairs" pairsCommonState
+
+indexCommonState :: CommonState -> AnyValue -> Lua Lua.NumResults
+indexCommonState st (AnyValue idx) = Lua.ltype idx >>= \case
+  Lua.TypeString -> 1 <$ (Lua.peek idx >>= pushField)
+  _ -> 1 <$ Lua.pushnil
+ where
+  pushField :: String -> Lua ()
+  pushField name = case lookup name commonStateFields of
+    Just pushValue -> pushValue st
+    Nothing -> Lua.pushnil
+
+pairsCommonState :: CommonState -> Lua Lua.NumResults
+pairsCommonState st = do
+  Lua.pushHaskellFunction nextFn
+  Lua.pushnil
+  Lua.pushnil
+  return 3
+ where
+  nextFn :: AnyValue -> AnyValue -> Lua Lua.NumResults
+  nextFn _ (AnyValue idx) =
+    Lua.ltype idx >>= \case
+      Lua.TypeNil -> case commonStateFields of
+        []  -> 2 <$ (Lua.pushnil *> Lua.pushnil)
+        (key, pushValue):_ -> 2 <$ (Lua.push key *> pushValue st)
+      Lua.TypeString -> do
+        key <- Lua.peek idx
+        case tail $ dropWhile ((/= key) . fst) commonStateFields of
+          []                     -> 2 <$ (Lua.pushnil *> Lua.pushnil)
+          (nextKey, pushValue):_ -> 2 <$ (Lua.push nextKey *> pushValue st)
+      _ -> 2 <$ (Lua.pushnil *> Lua.pushnil)
+
+commonStateFields :: [(String, CommonState -> Lua ())]
+commonStateFields =
+  [ ("input_files", Lua.push . stInputFiles)
+  , ("output_file", Lua.push . Lua.Optional . stOutputFile)
+  , ("log", Lua.push . stLog)
+  , ("request_headers", Lua.push . Map.fromList . stRequestHeaders)
+  , ("resource_path", Lua.push . stResourcePath)
+  , ("source_url", Lua.push . Lua.Optional . stSourceURL)
+  , ("user_data_dir", Lua.push . Lua.Optional . stUserDataDir)
+  , ("trace", Lua.push . stTrace)
+  , ("verbosity", Lua.push . show . stVerbosity)
+  ]
+
+-- | Name used by Lua for the @CommonState@ type.
+logMessageTypeName :: String
+logMessageTypeName = "Pandoc LogMessage"
+
+instance Peekable LogMessage where
+  peek idx = reportValueOnFailure logMessageTypeName
+             (`toAnyWithName` logMessageTypeName) idx
+
+instance Pushable LogMessage where
+  push msg = pushAnyWithMetatable pushLogMessageMetatable msg
+   where
+    pushLogMessageMetatable = ensureUserdataMetatable logMessageTypeName $
+      LuaUtil.addFunction "__tostring" tostringLogMessage
+
+tostringLogMessage :: LogMessage -> Lua String
+tostringLogMessage = return . showLogMessage
diff --git a/src/Text/Pandoc/Lua/Marshaling/ReaderOptions.hs b/src/Text/Pandoc/Lua/Marshaling/ReaderOptions.hs
new file mode 100644
index 000000000..5395f6fc8
--- /dev/null
+++ b/src/Text/Pandoc/Lua/Marshaling/ReaderOptions.hs
@@ -0,0 +1,79 @@
+{-# LANGUAGE NoImplicitPrelude    #-}
+{-# LANGUAGE FlexibleInstances    #-}
+{-# LANGUAGE ScopedTypeVariables  #-}
+{-# LANGUAGE LambdaCase           #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+{- |
+   Module      : Text.Pandoc.Lua.Marshaling.ReaderOptions
+   Copyright   : © 2012-2019 John MacFarlane
+                 © 2017-2019 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+Marshaling instance for ReaderOptions and its components.
+-}
+module Text.Pandoc.Lua.Marshaling.ReaderOptions () where
+
+import Prelude
+import Data.Data (showConstr, toConstr)
+import Foreign.Lua (Lua, Pushable)
+import Text.Pandoc.Extensions (Extensions)
+import Text.Pandoc.Lua.Marshaling.AnyValue (AnyValue (..))
+import Text.Pandoc.Lua.Marshaling.CommonState ()
+import Text.Pandoc.Options (ReaderOptions (..), TrackChanges)
+
+import qualified Data.Set as Set
+import qualified Foreign.Lua as Lua
+import qualified Text.Pandoc.Lua.Util as LuaUtil
+
+--
+-- Reader Options
+--
+instance Pushable Extensions where
+  push exts = Lua.push (show exts)
+
+instance Pushable TrackChanges where
+  push = Lua.push . showConstr . toConstr
+
+instance Pushable ReaderOptions where
+  push ro = do
+    let ReaderOptions
+          (extensions            :: Extensions)
+          (standalone            :: Bool)
+          (columns               :: Int)
+          (tabStop               :: Int)
+          (indentedCodeClasses   :: [String])
+          (abbreviations         :: Set.Set String)
+          (defaultImageExtension :: String)
+          (trackChanges          :: TrackChanges)
+          (stripComments         :: Bool)
+          = ro
+    Lua.newtable
+    LuaUtil.addField "extensions" extensions
+    LuaUtil.addField "standalone" standalone
+    LuaUtil.addField "columns" columns
+    LuaUtil.addField "tab_stop" tabStop
+    LuaUtil.addField "indented_code_classes" indentedCodeClasses
+    LuaUtil.addField "abbreviations" abbreviations
+    LuaUtil.addField "default_image_extension" defaultImageExtension
+    LuaUtil.addField "track_changes" trackChanges
+    LuaUtil.addField "strip_comments" stripComments
+
+    -- add metatable
+    let indexReaderOptions :: AnyValue -> AnyValue -> Lua Lua.NumResults
+        indexReaderOptions _tbl (AnyValue key) = do
+          Lua.ltype key >>= \case
+            Lua.TypeString -> Lua.peek key >>= \case
+              "defaultImageExtension" -> Lua.push defaultImageExtension
+              "indentedCodeClasses" -> Lua.push indentedCodeClasses
+              "stripComments" -> Lua.push stripComments
+              "tabStop" -> Lua.push tabStop
+              "trackChanges" -> Lua.push trackChanges
+              _ -> Lua.pushnil
+            _ -> Lua.pushnil
+          return 1
+    Lua.newtable
+    LuaUtil.addFunction "__index" indexReaderOptions
+    Lua.setmetatable (Lua.nthFromTop 2)
diff --git a/src/Text/Pandoc/Lua/Module/MediaBag.hs b/src/Text/Pandoc/Lua/Module/MediaBag.hs
index eabab11ed..a9813b958 100644
--- a/src/Text/Pandoc/Lua/Module/MediaBag.hs
+++ b/src/Text/Pandoc/Lua/Module/MediaBag.hs
@@ -36,7 +36,7 @@ import Data.Maybe (fromMaybe)
 import Foreign.Lua (Lua, NumResults, Optional, liftIO)
 import Text.Pandoc.Class (CommonState (..), fetchItem, putCommonState,
                           runIOorExplode, setMediaBag)
-import Text.Pandoc.Lua.StackInstances ()
+import Text.Pandoc.Lua.Marshaling ()
 import Text.Pandoc.Lua.Util (addFunction)
 import Text.Pandoc.MIME (MimeType)
 
diff --git a/src/Text/Pandoc/Lua/Module/Pandoc.hs b/src/Text/Pandoc/Lua/Module/Pandoc.hs
index 30e36af9d..b28b112d5 100644
--- a/src/Text/Pandoc/Lua/Module/Pandoc.hs
+++ b/src/Text/Pandoc/Lua/Module/Pandoc.hs
@@ -41,7 +41,7 @@ import System.Exit (ExitCode (..))
 import Text.Pandoc.Class (runIO)
 import Text.Pandoc.Definition (Block, Inline)
 import Text.Pandoc.Lua.Filter (walkInlines, walkBlocks, LuaFilter)
-import Text.Pandoc.Lua.StackInstances ()
+import Text.Pandoc.Lua.Marshaling ()
 import Text.Pandoc.Walk (Walkable)
 import Text.Pandoc.Options (ReaderOptions (readerExtensions))
 import Text.Pandoc.Process (pipeProcess)
diff --git a/src/Text/Pandoc/Lua/Module/Utils.hs b/src/Text/Pandoc/Lua/Module/Utils.hs
index 101a33809..c9df996ac 100644
--- a/src/Text/Pandoc/Lua/Module/Utils.hs
+++ b/src/Text/Pandoc/Lua/Module/Utils.hs
@@ -38,7 +38,7 @@ import Foreign.Lua (Peekable, Lua, NumResults)
 import Text.Pandoc.Class (runIO, setUserDataDir)
 import Text.Pandoc.Definition ( Pandoc, Meta, MetaValue (..), Block, Inline
                               , Citation, Attr, ListAttributes)
-import Text.Pandoc.Lua.StackInstances ()
+import Text.Pandoc.Lua.Marshaling ()
 import Text.Pandoc.Lua.Util (addFunction)
 
 import qualified Data.Digest.Pure.SHA as SHA