src/Text/Pandoc/Lua/Marshaling/AnyValue.hs


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{-# LANGUAGE NoImplicitPrelude    #-}
{- |
   Module      : Text.Pandoc.Lua.Marshaling.AnyValue
   Copyright   : © 2017-2020 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