diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Text/Pandoc/Lua.hs | 91 |
1 files changed, 58 insertions, 33 deletions
diff --git a/src/Text/Pandoc/Lua.hs b/src/Text/Pandoc/Lua.hs index d7c54b6af..ccd820682 100644 --- a/src/Text/Pandoc/Lua.hs +++ b/src/Text/Pandoc/Lua.hs @@ -15,6 +15,9 @@ 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 FlexibleContexts #-} +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE OverloadedStrings #-} {- | Module : Text.Pandoc.Lua @@ -130,29 +133,35 @@ execInlineLuaFilter :: LuaState -> HashMap Text (LuaFilterFunction Inline) -> Inline -> IO Inline execInlineLuaFilter lua fnMap x = do - let filterOrId constr = case HashMap.lookup constr fnMap of - Nothing -> return x - Just fn -> runLuaFilterFunction lua fn x + let runFn :: PushViaFilterFunction Inline a => LuaFilterFunction Inline -> a + runFn fn = runLuaFilterFunction lua fn + let tryFilter :: Text -> (LuaFilterFunction Inline -> IO Inline) -> IO Inline + tryFilter fnName callFilterFn = + case HashMap.lookup fnName fnMap of + Nothing -> return x + Just fn -> callFilterFn fn case x of - Cite _ _ -> filterOrId "Cite" - Code _ _ -> filterOrId "Code" - Emph _ -> filterOrId "Emph" - Image _ _ _ -> filterOrId "Image" - LineBreak -> filterOrId "LineBreak" - Link _ _ _ -> filterOrId "Link" - Math _ _ -> filterOrId "Math" - Note _ -> filterOrId "Note" - Quoted _ _ -> filterOrId "Quoted" - RawInline _ _ -> filterOrId "RawInline" - SmallCaps _ -> filterOrId "SmallCaps" - SoftBreak -> filterOrId "SoftBreak" - Space -> filterOrId "Space" - Span _ _ -> filterOrId "Span" - Str _ -> filterOrId "Str" - Strikeout _ -> filterOrId "Strikeout" - Strong _ -> filterOrId "Strong" - Subscript _ -> filterOrId "Subscript" - Superscript _ -> filterOrId "Superscript" + LineBreak -> tryFilter "LineBreak" runFn + SoftBreak -> tryFilter "SoftBreak" runFn + Space -> tryFilter "Space" runFn + Cite cs lst -> tryFilter "Cite" $ \fn -> runFn fn lst cs + Code attr str -> tryFilter "Code" $ \fn -> runFn fn str attr + Emph lst -> tryFilter "Emph" $ \fn -> runFn fn lst + Math mt lst -> tryFilter "Math" $ \fn -> runFn fn lst mt + Note blks -> tryFilter "Note" $ \fn -> runFn fn blks + Quoted qt lst -> tryFilter "Quoted" $ \fn -> runFn fn qt lst + RawInline f str -> tryFilter "RawInline" $ \fn -> runFn fn f str + SmallCaps lst -> tryFilter "SmallCaps" $ \fn -> runFn fn lst + Span attr lst -> tryFilter "Span" $ \fn -> runFn fn lst attr + Str str -> tryFilter "Str" $ \fn -> runFn fn str + Strikeout lst -> tryFilter "Strikeout" $ \fn -> runFn fn lst + Strong lst -> tryFilter "Strong" $ \fn -> runFn fn lst + Subscript lst -> tryFilter "Subscript" $ \fn -> runFn fn lst + Superscript lst -> tryFilter "Superscript" $ \fn -> runFn fn lst + Link attr txt (src, tit) -> tryFilter "Link" $ + \fn -> runFn fn txt src tit attr + Image attr alt (src, tit) -> tryFilter "Image" $ + \fn -> runFn fn alt src tit attr instance StackValue LuaFilter where valuetype _ = Lua.TTABLE @@ -164,17 +173,33 @@ instance StackValue LuaFilter where docFnMap <- Lua.peek lua i return $ LuaFilter lua <$> inlineFnMap <*> blockFnMap <*> docFnMap -runLuaFilterFunction :: (StackValue a) - => LuaState -> LuaFilterFunction a -> a -> IO a -runLuaFilterFunction lua lf inline = do - pushFilterFunction lua lf - Lua.push lua inline - Lua.call lua 1 1 - mbres <- Lua.peek lua (-1) - case mbres of - Nothing -> error $ "Error while trying to get a filter's return " - ++ "value from lua stack." - Just res -> res <$ Lua.pop lua 1 +-- | Helper class for pushing a single value to the stack via a lua function. +-- See @pushViaCall@. +class PushViaFilterFunction a b where + pushViaFilterFunction' :: LuaState -> LuaFilterFunction a -> IO () -> Int -> b + +instance (StackValue a) => PushViaFilterFunction a (IO a) where + pushViaFilterFunction' lua lf pushArgs num = do + pushFilterFunction lua lf + pushArgs + Lua.call lua num 1 + mbres <- Lua.peek lua (-1) + case mbres of + Nothing -> error $ "Error while trying to get a filter's return " + ++ "value from lua stack." + Just res -> res <$ Lua.pop lua 1 + +instance (PushViaFilterFunction a c, StackValue b) => + PushViaFilterFunction a (b -> c) where + pushViaFilterFunction' lua lf pushArgs num x = + pushViaFilterFunction' lua lf (pushArgs *> push lua x) (num + 1) + +-- | Push an value to the stack via a lua filter function. The function is +-- called with all arguments that are passed to this function and is expected to +-- return a single value. +runLuaFilterFunction :: (StackValue a, PushViaFilterFunction a b) + => LuaState -> LuaFilterFunction a -> b +runLuaFilterFunction lua lf = pushViaFilterFunction' lua lf (return ()) 0 -- | Push the filter function to the top of the stack. pushFilterFunction :: Lua.LuaState -> LuaFilterFunction a -> IO () |