add alt blockquote syntax to langfilter

"""
like this
"""

langfilter/Main.hs

@@ -8,9 +8,11 @@ import Glosses
 import Text.Pandoc.Definition
 import Text.Pandoc.JSON
 import Text.Pandoc.Walk
+import Data.Maybe
 import qualified Data.Map as Map
-import Control.Applicative
 import qualified Data.Text as Text
+import Control.Applicative
+import Control.Monad
 
 
 main :: IO ()
@@ -19,6 +21,7 @@ main = toJSONFilter filter where
     lang' <- toLang $ Map.lookup "conlang" m
     let ?lang = lang'
     fmap (walk makeEbnf .
+          walk makeQuotes .
           walk (concatMap makeBlocks) .
           walk inlineLetterList) $
       walkM spans =<<
@@ -39,12 +42,30 @@ makeBlocks :: Block -> [Block]
 makeBlocks (Div ("", clss, []) blks)
   | Just (cls, rest) <- pluck1 ["figure", "aside"] clss =
       let html  = RawBlock $ Format "html"
-          open  = html $ "<" <> cls <> " class='" <> Text.unwords rest <> "'>"
+          open  = if null rest then
+                    html $ "<" <> cls <> ">"
+                  else
+                    html $ "<" <> cls <> " class='" <> Text.unwords rest <> "'>"
           close = html $ "</" <> cls <> ">"
       in
       [open] ++ blks ++ [close]
 makeBlocks b = [b]
 
+makeQuotes :: Block -> Block
+makeQuotes para@(Para b) = fromMaybe para $ do
+    inner <- split b
+    return (BlockQuote [Para inner])
+  where
+    isDelim str = str == "\"\"\"" || str == "““”" -- lol
+
+    split (Str begin:SoftBreak:rest) = guard (isDelim begin) *> checkEnd rest
+    split _                          = empty
+
+    checkEnd [SoftBreak, Str end] = [] <$ guard (isDelim end)
+    checkEnd (start:rest)         = (start :) <$> checkEnd rest
+    checkEnd _                    = empty
+makeQuotes other = other
+
 
 inlineLetterList :: Block -> Block
 inlineLetterList (Div a@(_, cs, _) blks)