X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FErr.lhs;h=803fdf0b518a5a6f1865227642a2451e0b2f7555;hb=19de173b1bd4fa8cf1854cfefa619565910137f3;hp=43834aa5698b3000ed2de7e9582e05ae7425d20c;hpb=3d2db48412b8f469ba4943f95b0dce9354de4afb;p=ghc-base.git

diff --git a/GHC/Err.lhs b/GHC/Err.lhs
index 43834aa..803fdf0 100644
--- a/GHC/Err.lhs
+++ b/GHC/Err.lhs
@@ -30,6 +30,7 @@ module GHC.Err
        , runtimeError              -- :: Addr#  -> a	-- Addr# points to UTF8 encoded C string
 
        , absentErr	           -- :: a
+       , divZeroError		   -- :: a
 
        , error		           -- :: String -> a
        , assertError		   -- :: String -> Bool -> a -> a
@@ -51,12 +52,13 @@ import GHC.Exception
 %*********************************************************
 
 \begin{code}
--- error stops execution and displays an error message
+-- | 'error' stops execution and displays an error message.
 error :: String -> 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
@@ -126,3 +128,13 @@ untangle coded message
 	}
     not_bar c = c /= '|'
 \end{code}
+
+Divide by zero.  We put it here because it is needed relatively early
+in the libraries before the Exception type has been defined yet.
+
+\begin{code}
+{-# NOINLINE divZeroError #-}
+divZeroError :: a
+divZeroError = throw (ArithException DivideByZero)
+\end{code}
+