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diff --git a/src/Text/Pandoc/Lua/Marshal/PandocError.hs b/src/Text/Pandoc/Lua/Marshal/PandocError.hs
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+++ b/src/Text/Pandoc/Lua/Marshal/PandocError.hs
@@ -0,0 +1,51 @@
+{-# LANGUAGE LambdaCase           #-}
+{-# LANGUAGE OverloadedStrings    #-}
+{-# LANGUAGE ScopedTypeVariables  #-}
+{-# LANGUAGE TypeApplications     #-}
+{- |
+   Module      : Text.Pandoc.Lua.Marshal.PandocError
+   Copyright   : © 2020-2021 Albert Krewinkel
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>
+   Stability   : alpha
+
+Marshal of @'PandocError'@ values.
+-}
+module Text.Pandoc.Lua.Marshal.PandocError
+  ( peekPandocError
+  , pushPandocError
+  , typePandocError
+  )
+  where
+
+import HsLua.Core (LuaError)
+import HsLua.Marshalling (Peeker, Pusher, pushString, liftLua)
+import HsLua.Packaging
+import Text.Pandoc.Error (PandocError (PandocLuaError))
+
+import qualified HsLua as Lua
+import qualified Text.Pandoc.UTF8 as UTF8
+
+-- | Lua userdata type definition for PandocError.
+typePandocError :: LuaError e => DocumentedType e PandocError
+typePandocError = deftype "PandocError"
+  [ operation Tostring $ defun "__tostring"
+    ### liftPure (show @PandocError)
+    <#> udparam typePandocError "obj" "PandocError object"
+    =#> functionResult pushString "string" "string representation of error."
+  ]
+  mempty -- no members
+
+-- | Peek a @'PandocError'@ element to the Lua stack.
+pushPandocError :: LuaError e => Pusher e PandocError
+pushPandocError = pushUD typePandocError
+
+-- | Retrieve a @'PandocError'@ from the Lua stack.
+peekPandocError :: LuaError e => Peeker e PandocError
+peekPandocError idx = Lua.retrieving "PandocError" $
+  liftLua (Lua.ltype idx) >>= \case
+    Lua.TypeUserdata -> peekUD typePandocError idx
+    _ -> do
+      msg <- liftLua $ Lua.state >>= \l -> Lua.liftIO (Lua.popErrorMessage l)
+      return $ PandocLuaError (UTF8.toText msg)