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diff --git a/src/Text/Pandoc/Lua/Marshaling/List.hs b/src/Text/Pandoc/Lua/Marshaling/List.hs
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+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE DeriveDataTypeable   #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE NoImplicitPrelude    #-}
+{-# LANGUAGE UndecidableInstances #-}
+{- |
+Module      : Text.Pandoc.Lua.Marshaling.List
+Copyright   : © 2012-2020 John MacFarlane
+              © 2017-2020 Albert Krewinkel
+License     : GNU GPL, version 2 or above
+Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+Stability   : alpha
+
+Marshaling/unmarshaling instances for @pandoc.List@s.
+-}
+module Text.Pandoc.Lua.Marshaling.List
+  ( List (..)
+  ) where
+
+import Prelude
+import Data.Data (Data)
+import Foreign.Lua (Peekable, Pushable)
+import Text.Pandoc.Walk (Walkable (..))
+import Text.Pandoc.Lua.Util (defineHowTo, pushViaConstructor)
+
+import qualified Foreign.Lua as Lua
+
+-- | List wrapper which is marshalled as @pandoc.List@.
+newtype List a = List { fromList :: [a] }
+  deriving (Data, Eq, Show)
+
+instance Pushable a => Pushable (List a) where
+  push (List xs) =
+    pushViaConstructor "List" xs
+
+instance Peekable a => Peekable (List a) where
+  peek idx = defineHowTo "get List" $ do
+    xs <- Lua.peek idx
+    return $ List xs
+
+-- List is just a wrapper, so we can reuse the walk instance for
+-- unwrapped Hasekll lists.
+instance Walkable [a] b => Walkable (List a) b where
+  walkM f = walkM (fmap fromList . f . List)
+  query f = query (f . List)