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+-- cabal-helper: Simple interface to Cabal's configuration state
+-- Copyright (C) 2018 Daniel Gröber <cabal-helper@dxld.at>
+--
+-- 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 <http://www.gnu.org/licenses/>.
+
+{-|
+Module : CabalHelper.Compiletime.Log
+Description : Logging utilities
+License : GPL-3
+-}
+
+module CabalHelper.Compiletime.Log where
+
+import Control.Monad.IO.Class
+import System.IO
+import System.IO.Error
+
+import CabalHelper.Compiletime.Types
+
+logIOError :: Verbose => String -> IO (Maybe a) -> IO (Maybe a)
+logIOError label a = do
+ a `catchIOError` \ex -> do
+ vLog $ label ++ ": " ++ show ex
+ return Nothing
+
+vLog :: (MonadIO m, Verbose) => String -> m ()
+vLog msg
+ | ?verbose = liftIO $ hPutStrLn stderr msg
+ | otherwise = return ()