\begin{code}
module Panic
(
- GhcException(..), ghcError, progName,
- panic, panic#, assertPanic, trace,
- showException, showGhcException, Exception.throwDyn, tryMost,
-
- Exception.Exception,
- Panic.try, -- try :: IO a -> IO (Either Exception a)
- -- This is Control.Exception.try in the new library story
- -- Exception.tryAllIO in GHC 4.08
- -- So it usefully hides the difference
+ GhcException(..), showGhcException, ghcError, progName,
+ pgmError,
-#if __GLASGOW_HASKELL__ <= 408
+ panic, panic#, assertPanic, trace,
+
+ Exception.Exception(..), showException, try, tryJust, tryMost, tryUser,
catchJust, ioErrors, throwTo,
-#endif
+
+ installSignalHandlers,
) where
#include "HsVersions.h"
import Config
import FastTypes
+#ifndef mingw32_HOST_OS
+# if __GLASGOW_HASKELL__ > 504
+import System.Posix.Signals
+# else
+import Posix ( Handler(Catch), installHandler, sigINT, sigQUIT )
+# endif /* GHC > 504 */
+#endif /* mingw32_HOST_OS */
+
+#if defined(mingw32_HOST_OS) && __GLASGOW_HASKELL__ >= 603
+import GHC.ConsoleHandler
+#endif
+
+# if __GLASGOW_HASKELL__ < 500
+import EXCEPTION ( raiseInThread )
+# else
+import EXCEPTION ( throwTo )
+# endif /* GHC < 500 */
+
+#if __GLASGOW_HASKELL__ > 408
+import EXCEPTION ( catchJust, tryJust, ioErrors )
+#endif
+
+import CONCURRENT ( myThreadId )
import DYNAMIC
import qualified EXCEPTION as Exception
import TRACE ( trace )
import UNSAFE_IO ( unsafePerformIO )
+import IO ( isUserError )
import System
\end{code}
= showString ("panic! (the `impossible' happened, GHC version "
++ cProjectVersion ++ "):\n\t"
++ s ++ "\n\n"
- ++ "Please report it as a compiler bug "
- ++ "to glasgow-haskell-bugs@haskell.org,\n"
- ++ "or http://sourceforge.net/projects/ghc/.\n\n")
+ ++ "Please report this as a compiler bug. See:\n"
+ ++ " http://www.haskell.org/ghc/docs/latest/html/users_guide/bug-reporting.html\n")
+
+#if __GLASGOW_HASKELL__ < 603
+myMkTyConApp = mkAppTy
+#else
+myMkTyConApp = mkTyConApp
+#endif
ghcExceptionTc = mkTyCon "GhcException"
{-# NOINLINE ghcExceptionTc #-}
instance Typeable GhcException where
- typeOf _ = mkAppTy ghcExceptionTc []
+ typeOf _ = myMkTyConApp ghcExceptionTc []
\end{code}
Panics and asserts.
\begin{code}
-panic :: String -> a
-panic x = Exception.throwDyn (Panic x)
+panic, pgmError :: String -> a
+panic x = Exception.throwDyn (Panic x)
+pgmError x = Exception.throwDyn (ProgramError x)
--- #-versions because panic can't return an unboxed int, and that's
+-- #-versions because panic can't return an unboxed int, and that's
-- what TAG_ is with GHC at the moment. Ugh. (Simon)
-- No, man -- Too Beautiful! (Will)
filter other
= return other
+-- | tryUser is like try, but catches only UserErrors.
+-- These are the ones that are thrown by the TcRn monad
+-- to signal an error in the program being compiled
+tryUser :: IO a -> IO (Either Exception.Exception a)
+tryUser action = tryJust tc_errors action
+ where
+#if __GLASGOW_HASKELL__ > 504 || __GLASGOW_HASKELL__ < 500
+ tc_errors e@(Exception.IOException ioe) | isUserError ioe = Just e
+#elif __GLASGOW_HASKELL__ == 502
+ tc_errors e@(UserError _) = Just e
+#else
+ tc_errors e@(Exception.IOException ioe) | isUserError e = Just e
+#endif
+ tc_errors _other = Nothing
+\end{code}
+
+Compatibility stuff:
+
+\begin{code}
#if __GLASGOW_HASKELL__ <= 408
try = Exception.tryAllIO
#else
try = Exception.try
#endif
-\end{code}
-Compatibility stuff:
+#if __GLASGOW_HASKELL__ <= 408
+catchJust = Exception.catchIO
+tryJust = Exception.tryIO
+ioErrors = Exception.justIoErrors
+throwTo = Exception.raiseInThread
+#endif
+\end{code}
+
+Standard signal handlers for catching ^C, which just throw an
+exception in the main thread. NOTE: must be called from the main
+thread.
\begin{code}
-#if __GLASGOW_HASKELL__ <= 408
-catchJust = catchIO
-ioErrors = justIoErrors
-throwTo = raiseInThread
+installSignalHandlers :: IO ()
+installSignalHandlers = do
+ main_thread <- myThreadId
+ let
+ interrupt_exn = Exception.DynException (toDyn Interrupted)
+ interrupt = throwTo main_thread interrupt_exn
+ --
+#if !defined(mingw32_HOST_OS)
+ installHandler sigQUIT (Catch interrupt) Nothing
+ installHandler sigINT (Catch interrupt) Nothing
+ return ()
+#elif __GLASGOW_HASKELL__ >= 603
+ -- GHC 6.3+ has support for console events on Windows
+ -- NOTE: running GHCi under a bash shell for some reason requires
+ -- you to press Ctrl-Break rather than Ctrl-C to provoke
+ -- an interrupt. Ctrl-C is getting blocked somewhere, I don't know
+ -- why --SDM 17/12/2004
+ let sig_handler ControlC = interrupt
+ sig_handler Break = interrupt
+ sig_handler _ = return ()
+
+ installHandler (Catch sig_handler)
+ return ()
+#else
+ return () -- nothing
#endif
\end{code}