-- >>

-- <<waitCatchSTM
waitCatchSTM :: Async a -> STM (Either SomeException a)
waitCatchSTM (Async _ var) = readTMVar var
waitCatchSTM :: Async a -> STM (Either SomeException a)
waitCatchSTM (Async _ var) = readTMVar var
waitCatchSTM (Async _ var) = readTMVar var