[project @ 2001-03-01 15:59:51 by simonmar]

[ghc-hetmet.git] / ghc / compiler / utils / Panic.lhs

diff --git a/ghc/compiler/utils/Panic.lhs b/ghc/compiler/utils/Panic.lhs
index c3e4865..81818df 100644 (file)
--- a/ghc/compiler/utils/Panic.lhs
+++ b/ghc/compiler/utils/Panic.lhs
@@ -1,5 +1,5 @@
 %
-% (c) The GRASP Project, Glasgow University, 1992-1998
+% (c) The GRASP Project, Glasgow University, 1992-2000
 %
 \section{Panic error messages}
 
@@ -9,27 +9,81 @@ It's hard to put these functions anywhere else without causing
 some unnecessary loops in the module dependency graph.
 
 \begin{code}
-module Panic ( panic, panic#, assertPanic, trace ) where
+module Panic  
+   ( 
+     GhcException(..), ghcError, progName, 
+     panic, panic#, assertPanic, trace 
+   ) where
 
-import GlaExts( trace )
+import Config
+import FastTypes
 
+import Dynamic
+import IOExts
+import Exception
+
+import System
 #include "HsVersions.h"
 \end{code}
 
+GHC's own exception type.
+
+\begin{code}
+ghcError :: GhcException -> a
+ghcError e = throwDyn e
+
+data GhcException
+  = PhaseFailed String ExitCode
+  | Interrupted
+  | UsageError String          -- prints the short usage msg after the error
+  | Panic String               -- the `impossible' happened
+  | OtherError String          -- just prints the error message
+  deriving Eq
+
+progName = unsafePerformIO (getProgName)
+{-# NOINLINE progName #-}
+
+short_usage = "Usage: For basic information, try the `--help' option."
+   
+instance Show GhcException where
+  showsPrec _ e = showString progName . showString ": " . showBarf e
+
+showBarf (UsageError str)
+   = showString str . showChar '\n' . showString short_usage
+showBarf (OtherError str)
+   = showString str
+showBarf (PhaseFailed phase code)
+   = showString phase . showString " failed, code = " . shows code
+showBarf (Interrupted)
+   = showString "interrupted"
+showBarf (Panic s)
+   = 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\n")
+
+ghcExceptionTc = mkTyCon "GhcException"
+{-# NOINLINE ghcExceptionTc #-}
+instance Typeable GhcException where
+  typeOf _ = mkAppTy ghcExceptionTc []
+\end{code}
+
+Panics and asserts.
+
 \begin{code}
 panic :: String -> a
-panic x = error ("panic! (the `impossible' happened):\n\t"
-             ++ x ++ "\n\n"
-             ++ "Please report it as a compiler bug "
-             ++ "to glasgow-haskell-bugs@dcs.gla.ac.uk.\n\n" )
+panic x = throwDyn (Panic x)
 
 -- #-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)
 
-panic# :: String -> FAST_INT
-panic# s = case (panic s) of () -> ILIT(0)
+panic# :: String -> FastInt
+panic# s = case (panic s) of () -> _ILIT 0
 
 assertPanic :: String -> Int -> a
-assertPanic file line = panic ("ASSERT failed! file " ++ file ++ ", line " ++ show line)
+assertPanic file line = 
+  throw (AssertionFailed 
+           ("ASSERT failed! file " ++ file ++ ", line " ++ show line))
 \end{code}