-- Copyright (C) 2017-2018 Daniel Gröber -- -- This program is free software: you can redistribute it and/or modify -- it under the terms of the GNU General Public License as published by -- the Free Software Foundation, either version 3 of the License, or -- (at your option) any later version. -- -- This program is distributed in the hope that it will be useful, -- but WITHOUT ANY WARRANTY; without even the implied warranty of -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -- GNU General Public License for more details. -- -- You should have received a copy of the GNU General Public License -- along with this program. If not, see . {-# LANGUAGE ScopedTypeVariables #-} {-| Module : CabalHelper.Compiletime.Log Description : Basic logging facilities License : GPL-3 -} module CabalHelper.Compiletime.Log where import Control.Monad import Control.Monad.IO.Class import Control.Exception as E import Data.String import System.IO import Prelude import CabalHelper.Compiletime.Types vLog :: MonadIO m => Options -> String -> m () vLog Options { oVerbose = True } msg = liftIO $ hPutStrLn stderr msg vLog _ _ = return () logIOError :: Options -> String -> IO (Maybe a) -> IO (Maybe a) logIOError opts label a = do a `E.catch` \(ex :: IOError) -> do vLog opts $ label ++ ": " ++ show ex return Nothing