Added a type signature

1 files changed, 2 insertions, 1 deletions

diff --git a/pandoc.hs b/pandoc.hs
index 492d49b10..18d36b223 100644
--- a/pandoc.hs
+++ b/pandoc.hs
@@ -1439,7 +1439,8 @@ convertWithOpts opts args = do
         mapM_ (warn . ("Ignoring: " ++)) xs
         liftIO $ B.readFile x
 
-  let runIO' f = do
+  let runIO' :: PandocIO a -> IO a
+      runIO' f = do
         (res, warnings) <- runIOorExplode $ do
                              x <- f
                              ws <- getWarnings