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diff --git a/src/Text/Pandoc/Lua/StackInstances.hs b/src/Text/Pandoc/Lua/StackInstances.hs
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+{-
+Copyright © 2012-2015 John MacFarlane <jgm@berkeley.edu>
+            2017 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
+-}
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE LambdaCase #-}
+#if !MIN_VERSION_base(4,8,0)
+{-# LANGUAGE OverlappingInstances #-}
+#endif
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+{- |
+   Module      : Text.Pandoc.Lua.StackInstances
+   Copyright   : Copyright © 2017 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+StackValue instances for pandoc types.
+-}
+module Text.Pandoc.Lua.StackInstances () where
+
+import Data.Aeson ( FromJSON(..), ToJSON(..), Result(..), Value, fromJSON )
+import Scripting.Lua ( StackValue(..) )
+import Scripting.Lua.Aeson ()
+import Text.Pandoc.Definition ( Block(..), Inline(..), Pandoc(..) )
+
+import qualified Scripting.Lua as Lua
+import qualified Text.Pandoc.UTF8 as UTF8
+
+maybeFromJson :: (FromJSON a) => Maybe Value -> Maybe a
+maybeFromJson mv = fromJSON <$> mv >>= \case
+  Success x -> Just x
+  _         -> Nothing
+
+instance StackValue Pandoc where
+  push lua = Lua.push lua . toJSON
+  peek lua i = maybeFromJson <$> peek lua i
+  valuetype _ = Lua.TTABLE
+
+instance StackValue Block where
+  push lua = Lua.push lua . toJSON
+  peek lua i = maybeFromJson <$> peek lua i
+  valuetype _ = Lua.TTABLE
+
+instance StackValue Inline where
+  push lua = Lua.push lua . toJSON
+  peek lua i = maybeFromJson <$> peek lua i
+  valuetype _ = Lua.TTABLE
+
+#if MIN_VERSION_base(4,8,0)
+instance {-# OVERLAPS #-} StackValue [Char] where
+#else
+instance StackValue [Char] where
+#endif
+  push lua cs = Lua.push lua (UTF8.fromString cs)
+  peek lua i = do
+                 res <- Lua.peek lua i
+                 return $ UTF8.toString `fmap` res
+  valuetype _ = Lua.TSTRING