Yana.hs

-- Example code

example :: (Context m, MonadLog m, AreaDao m) => [Actor] -> m ()
example list = 
  forM list $ \actor -> do
    logInfo $ "Actor being read: " ++ actorCode actor
    areaList <- getArea actor
    case areaList of
      [] -> return () -- do nothing
      (area : _) -> do
        setActorArea actor area
        logInfo $
          "Area{" ++ show area ++ "} is fetched for actor {" ++ actorCode actor ++ "}"
    setReadCount 1
    
-- Assumed preliminaries

data Actor
data Area

class MonadLog m
class AreaDao m
class Context m

logInfo :: MonadLog m => String -> m ()
actorCode :: Actor -> String
getArea :: AreaDao m => Actor -> m [Area]
setActorArea :: AreaDao m => Actor -> Area -> m ()
setReadCount :: Context m => Int -> m ()