Change TIOWorker to use TQueue

src/Quasar/Async/STMHelper.hs

@@ -14,13 +14,13 @@ import Quasar.Exceptions
 import Quasar.Prelude
 
 
-newtype TIOWorker = TIOWorker (TMVar (IO ()))
+newtype TIOWorker = TIOWorker (TQueue (IO ()))
 
 
 startTrivialIO :: forall a. TIOWorker -> ExceptionChannel -> IO a -> STM (Awaitable a)
-startTrivialIO (TIOWorker jobVar) exChan fn = do
+startTrivialIO (TIOWorker jobQueue) exChan fn = do
   resultVar <- newAsyncVarSTM
-  putTMVar jobVar $ job resultVar
+  writeTQueue jobQueue $ job resultVar
   pure $ toAwaitable resultVar
   where
     job :: AsyncVar a -> IO ()
@@ -37,11 +37,11 @@ startTrivialIO_ x y z = void $ startTrivialIO x y z
 
 newTIOWorker :: IO TIOWorker
 newTIOWorker = do
-  jobVar <- newEmptyTMVarIO
+  jobQueue <- newTQueueIO
   void $ forkIO $
-    handle
+    catch
+      (forever $ join $ atomically $ readTQueue jobQueue)
       -- Relies on garbage collection to remove the thread when it is no longer needed
       (\(_ :: BlockedIndefinitelyOnSTM) -> pure ())
-      (forever $ join $ atomically $ takeTMVar jobVar)
     
-  pure $ TIOWorker jobVar
+  pure $ TIOWorker jobQueue