From 08f53feceb1edb10f8b3a816021fb580b27e5b4c Mon Sep 17 00:00:00 2001
From: Tom Smeding <tom@tomsmeding.com>
Date: Fri, 19 Feb 2021 12:26:10 +0100
Subject: Write to stderr, not stdout

---
 Coolbal/Configure.hs | 2 +-
 Coolbal/FindRoot.hs  | 2 +-
 Coolbal/Target.hs    | 9 ++++-----
 Main.hs              | 3 ++-
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/Coolbal/Configure.hs b/Coolbal/Configure.hs
index 92865e7..d64b4b3 100644
--- a/Coolbal/Configure.hs
+++ b/Coolbal/Configure.hs
@@ -37,5 +37,5 @@ configure fname = do
           mapM_ (\d -> hPutStrLn stderr ("- " ++ show d)) deps
           exitFailure
       Right (pd, _flags) -> do
-          -- putStrLn ("Configured with flags: " ++ show flags)
+          -- hPutStrLn stderr ("Configured with flags: " ++ show flags)
           return pd
diff --git a/Coolbal/FindRoot.hs b/Coolbal/FindRoot.hs
index ea6e297..fb65491 100644
--- a/Coolbal/FindRoot.hs
+++ b/Coolbal/FindRoot.hs
@@ -23,7 +23,7 @@ findCabalSpec = do
     mfound <- findThingInDirs "cabal file" (`endsWith` ".cabal") doesFileExist FoundCabalSpec (ancestors cwd)
     case mfound of
       Just found -> do
-          putStrLn ("Found .cabal file: " ++ foundcsCabal found)
+          hPutStrLn stderr ("Found .cabal file: " ++ foundcsCabal found)
           return found
       Nothing -> do
           hPutStrLn stderr (".cabal file not found in ancestors of PWD: " ++ cwd)
diff --git a/Coolbal/Target.hs b/Coolbal/Target.hs
index 761f19d..64a0a16 100644
--- a/Coolbal/Target.hs
+++ b/Coolbal/Target.hs
@@ -111,17 +111,16 @@ instance IsTarget ExeTarget where
             ,map (intercalate ".") (exeTargetModules tg)
             ,["-o", binName]
             ,exeTargetFlags tg])
-          >>= checkExitCode "ghc"
+          >>= checkExitCode
 
     targetExecute tg = Just $ \projdir args -> do
         let filename = escapeFileName (exeTargetName tg)
         rawSystem (projdir </> "dist-coolbal/bin" </> filename) args
           >>= exitWith
 
-checkExitCode :: String -> ExitCode -> IO ()
-checkExitCode _ ExitSuccess = return ()
-checkExitCode procname (ExitFailure c) =
-    die (procname ++ " exited with code " ++ show c)
+checkExitCode :: ExitCode -> IO ()
+checkExitCode ExitSuccess = return ()
+checkExitCode c@(ExitFailure _) = exitWith c
 
 escapeFileName :: String -> FilePath
 escapeFileName =
diff --git a/Main.hs b/Main.hs
index c1f5f9b..b696241 100644
--- a/Main.hs
+++ b/Main.hs
@@ -14,6 +14,7 @@ import Options.Applicative (execParser)
 import System.Directory (createDirectoryIfMissing, removeDirectoryRecursive)
 import System.Exit (die)
 import System.FilePath ((</>))
+import System.IO (hPutStrLn, stderr)
 
 import Coolbal.CabalPlan
 import Coolbal.Configure (configure)
@@ -69,7 +70,7 @@ doConfigure = do
     -- print pd
     let targets = compatibleTargets pd plan
         names = map (useAnyTarget (\t -> targetName t ++ " (" ++ targetNameQualified t ++ ")")) targets
-    putStrLn ("Supported targets: " ++ intercalate ", " names)
+    hPutStrLn stderr ("Supported targets: " ++ intercalate ", " names)
 
     createDirectoryIfMissing True (foundcsRootDir foundSpec </> "dist-coolbal")
     B.encodeFile (foundcsRootDir foundSpec </> "dist-coolbal/targets.bin") targets
-- 
cgit v1.2.3-54-g00ecf