Put 'warn' in MonadIO. Add warnings for math conversions in docx.

src/Text/Pandoc/Shared.hs

@@ -127,6 +127,7 @@ import Text.Pandoc.MIME (MimeType, getMimeType)
 import System.FilePath ( (</>), takeExtension, dropExtension)
 import Data.Generics (Typeable, Data)
 import qualified Control.Monad.State as S
+import Control.Monad.Trans (MonadIO (..))
 import qualified Control.Exception as E
 import Control.Monad (msum, unless, MonadPlus(..))
 import Text.Pandoc.Pretty (charWidth)
@@ -974,7 +975,7 @@ openURL u
              UTF8.toString `fmap` lookup hContentType (responseHeaders resp))
 #else
   | otherwise = E.try $ getBodyAndMimeType `fmap` browse
-              (do S.liftIO $ UTF8.hPutStrLn stderr $ "Fetching " ++ u ++ "..."
+              (do liftIO $ UTF8.hPutStrLn stderr $ "Fetching " ++ u ++ "..."
                   setOutHandler $ const (return ())
                   setAllowRedirects True
                   request (getRequest' u'))
@@ -997,10 +998,10 @@ err exitCode msg = do
   exitWith $ ExitFailure exitCode
   return undefined
 
-warn :: String -> IO ()
-warn msg = do
+warn :: MonadIO m => String -> m ()
+warn msg = liftIO $ do
   name <- getProgName
-  UTF8.hPutStrLn stderr $ name ++ ": " ++ msg
+  UTF8.hPutStrLn stderr $ "[" ++ name ++ " warning] " ++ msg
 
 mapLeft :: (a -> b) -> Either a c -> Either b c
 mapLeft f (Left x) = Left (f x)

src/Text/Pandoc/Writers/Docx.hs

@@ -1115,7 +1115,9 @@ inlineToOpenXML' opts (Math mathType str) = do
   when (displayType == DisplayBlock) setFirstPara
   case writeOMML displayType <$> readTeX str of
         Right r -> return [r]
-        Left  _ -> inlinesToOpenXML opts (texMathToInlines mathType str)
+        Left  e -> do
+          warn $ "Cannot convert the following TeX math, skipping:\n" ++ str
+          inlinesToOpenXML opts (texMathToInlines mathType str)
 inlineToOpenXML' opts (Cite _ lst) = inlinesToOpenXML opts lst
 inlineToOpenXML' opts (Code attrs str) = do
   let unhighlighted = intercalate [br] `fmap`
@@ -1180,7 +1182,7 @@ inlineToOpenXML' opts (Image attr alt (src, title)) = do
                fetchItem' (writerMediaBag opts) (writerSourceURL opts) src
       case res of
         Left (_ :: E.SomeException) -> do
-          liftIO $ warn $ "Could not find image `" ++ src ++ "', skipping..."
+          warn $ "Could not find image `" ++ src ++ "', skipping..."
           -- emit alt text
           inlinesToOpenXML opts alt
         Right (img, mt) -> do

src/Text/Pandoc/Writers/ICML.hs

@@ -534,13 +534,13 @@ imageICML opts style attr (src, _) = do
   res  <- liftIO $ fetchItem (writerSourceURL opts) src
   imgS <- case res of
             Left (_) -> do
-              liftIO $ warn $ "Could not find image `" ++ src ++ "', skipping..."
+              warn $ "Could not find image `" ++ src ++ "', skipping..."
               return def
             Right (img, _) -> do
               case imageSize img of
                 Right size -> return size
                 Left msg   -> do
-                  return $ warn $ "Could not determine image size in `" ++
+                  warn $ "Could not determine image size in `" ++
                     src ++ "': " ++ msg
                   return def
   let (ow, oh) = sizeInPoints imgS