Add MonadIO to App.

1 files changed, 5 insertions, 3 deletions

diff --git a/src/Lib.hs b/src/Lib.hs
index 9748aed..695f0de 100644
--- a/src/Lib.hs
+++ b/src/Lib.hs
@@ -5,6 +5,7 @@ module Lib where
 
 import Control.Lens (makeLenses)
 import Control.Monad.Identity (Identity(..))
+import Control.Monad.IO.Class (MonadIO(..))
 import Control.Monad.Reader (ReaderT(..), runReaderT)
 import Control.Monad.Reader.Class (MonadReader(..))
 import Control.Monad.State.Class (MonadState(..))
@@ -35,14 +36,15 @@ instance Default World where
 makeLenses ''World
 
 newtype App a = App {
-      runApp :: StateT World (ReaderT Config Identity) a}
+      runApp :: StateT World (ReaderT Config IO) a}
     deriving ( Applicative
              , Functor
              , Monad
              , MonadState World
              , MonadReader Config
+             , MonadIO
              )
 
-evalApp :: App a -> World -> Config -> a
+evalApp :: App a -> World -> Config -> IO a
 evalApp f world config =
-    runIdentity (runReaderT (evalStateT (runApp f) world) config)
+    runReaderT (evalStateT (runApp f) world) config