checked-example1.hs

-- | example of monadic effectful  code that can throw multiple errors
simpleHttp
  :: forall m . (ThrowsMany m '[ HTTPException, DBException ], HttpNetwork m User)
  => Id -> m User
simpleHttp userId = do
  user <- getHttp userId
  case uId user of
     x | x == userId -> pure user
       | x == "Null" -> throwChecked DBException
       | otherwise   -> throwChecked HTTPException