X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FErr.lhs;h=90142f400ff76b775eb2f5550cf26380adbda4c9;hb=41e8fba828acbae1751628af50849f5352b27873;hp=fb34ab569b12d9096def1f7b619fdd3fb0fba052;hpb=05e43a9bd25232efced01ce45d00b3b3ba12af51;p=ghc-base.git

diff --git a/GHC/Err.lhs b/GHC/Err.lhs
index fb34ab5..90142f4 100644
--- a/GHC/Err.lhs
+++ b/GHC/Err.lhs
@@ -1,57 +1,58 @@
-% -----------------------------------------------------------------------------
-% $Id: Err.lhs,v 1.4 2002/04/11 12:03:43 simonpj Exp $
-%
-% (c) The University of Glasgow, 1994-2000
-%
-
-\section[GHC.Err]{Module @GHC.Err@}
-
-The GHC.Err module defines the code for the wired-in error functions,
-which have a special type in the compiler (with "open tyvars").
-
-We cannot define these functions in a module where they might be used
-(e.g., GHC.Base), because the magical wired-in type will get confused
-with what the typechecker figures out.
-
 \begin{code}
-{-# OPTIONS -fno-implicit-prelude #-}
-module GHC.Err 
+{-# LANGUAGE CPP, NoImplicitPrelude #-}
+{-# OPTIONS_HADDOCK hide #-}
+
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  GHC.Err
+-- Copyright   :  (c) The University of Glasgow, 1994-2002
+-- License     :  see libraries/base/LICENSE
+-- 
+-- Maintainer  :  cvs-ghc@haskell.org
+-- Stability   :  internal
+-- Portability :  non-portable (GHC extensions)
+--
+-- The "GHC.Err" module defines the code for the wired-in error functions,
+-- which have a special type in the compiler (with \"open tyvars\").
+-- 
+-- We cannot define these functions in a module where they might be used
+-- (e.g., "GHC.Base"), because the magical wired-in type will get confused
+-- with what the typechecker figures out.
+-- 
+-----------------------------------------------------------------------------
+
+-- #hide
+module GHC.Err
        (
-         irrefutPatError
-       , noMethodBindingError
-       , nonExhaustiveGuardsError
-       , patError
-       , recSelError
-       , recConError
-       , runtimeError              -- :: Addr#  -> a	-- Addr# points to UTF8 encoded C string
-
-       , absentErr, parError       -- :: a
-       , seqError                  -- :: a
-
-       , error		           -- :: String -> a
-       , assertError		   -- :: String -> Bool -> a -> a
-       
-       , undefined		   -- :: a
+         absentErr                 -- :: a
+       , divZeroError              -- :: a
+       , overflowError             -- :: a
+
+       , error                     -- :: String -> a
+
+       , undefined                 -- :: a
        ) where
 
-import GHC.Base
-import GHC.List     ( span )
+#ifndef __HADDOCK__
+import GHC.Types
 import GHC.Exception
+#endif
 \end{code}
 
 %*********************************************************
-%*							*
+%*                                                      *
 \subsection{Error-ish functions}
-%*							*
+%*                                                      *
 %*********************************************************
 
 \begin{code}
--- error stops execution and displays an error message
-error :: String -> a
+-- | 'error' stops execution and displays an error message.
+error :: [Char] -> a
 error s = throw (ErrorCall s)
 
+-- | A special case of 'error'.
 -- It is expected that compilers will recognize this and insert error
--- messages which are more appropriate to the context in which undefined 
+-- messages which are more appropriate to the context in which 'undefined'
 -- appears. 
 
 undefined :: a
@@ -59,67 +60,31 @@ undefined =  error "Prelude.undefined"
 \end{code}
 
 %*********************************************************
-%*							 *
+%*                                                       *
 \subsection{Compiler generated errors + local utils}
-%*							 *
+%*                                                       *
 %*********************************************************
 
 Used for compiler-generated error message;
 encoding saves bytes of string junk.
 
 \begin{code}
-absentErr, parError, seqError :: a
+absentErr :: a
 
 absentErr = error "Oops! The program has entered an `absent' argument!\n"
-parError  = error "Oops! Entered GHCerr.parError (a GHC bug -- please report it!)\n"
-seqError  = error "Oops! Entered seqError (a GHC bug -- please report it!)\n"
 \end{code}
 
-\begin{code}
-recSelError, recConError, irrefutPatError, runtimeError,
-	     nonExhaustiveGuardsError, patError, noMethodBindingError
-	:: Addr# -> a	-- All take a UTF8-encoded C string
-
-recSelError 		 s = throw (RecSelError (unpackCStringUtf8# s))	-- No location info unfortunately
-runtimeError		 s = error (unpackCStringUtf8# s)		-- No location info unfortunately
-
-nonExhaustiveGuardsError s = throw (PatternMatchFail (untangle s "Non-exhaustive guards in"))
-irrefutPatError		 s = throw (PatternMatchFail (untangle s "Irrefutable pattern failed for pattern"))
-recConError    		 s = throw (RecConError      (untangle s "Missing field in record construction"))
-noMethodBindingError     s = throw (NoMethodError    (untangle s "No instance nor default method for class operation"))
-patError 		 s = throw (PatternMatchFail (untangle s "Non-exhaustive patterns in"))
-
-assertError :: Addr# -> Bool -> a -> a
-assertError str pred v 
-  | pred      = v
-  | otherwise = throw (AssertionFailed (untangle str "Assertion failed"))
-\end{code}
-
-
-(untangle coded message) expects "coded" to be of the form 
-
-	"location|details"
-
-It prints
-
-	location message details
+Divide by zero and arithmetic overflow.
+We put them here because they are needed relatively early
+in the libraries before the Exception type has been defined yet.
 
 \begin{code}
-untangle :: Addr# -> String -> String
-untangle coded message
-  =  location
-  ++ ": " 
-  ++ message
-  ++ details
-  ++ "\n"
-  where
-    coded_str = unpackCStringUtf8# coded
-
-    (location, details)
-      = case (span not_bar coded_str) of { (loc, rest) ->
-	case rest of
-	  ('|':det) -> (loc, ' ' : det)
-	  _	    -> (loc, "")
-	}
-    not_bar c = c /= '|'
+{-# NOINLINE divZeroError #-}
+divZeroError :: a
+divZeroError = throw DivideByZero
+
+{-# NOINLINE overflowError #-}
+overflowError :: a
+overflowError = throw Overflow
 \end{code}
+