avoid versionitis in Numeric.showHex (should fix tcrun007)

[ghc-hetmet.git] / compiler / utils / Encoding.hs

diff --git a/compiler/utils/Encoding.hs b/compiler/utils/Encoding.hs
index 152bf3c..c7f9070 100644 (file)
--- a/compiler/utils/Encoding.hs
+++ b/compiler/utils/Encoding.hs
@@ -26,9 +26,9 @@ module Encoding (
 #define COMPILING_FAST_STRING
 #include "HsVersions.h"
 import Foreign
-import Data.Char       ( ord, chr, isDigit, digitToInt, isHexDigit )
-import Numeric         ( showHex )
-
+import Data.Char       ( ord, chr, isDigit, digitToInt, intToDigit,
+                         isHexDigit )
+import Numeric         ( showIntAtBase )
 import Data.Bits
 import GHC.Ptr         ( Ptr(..) )
 import GHC.Base
@@ -281,6 +281,9 @@ encode_ch c    = 'z' : if isDigit (head hex_str) then hex_str
   -- eg. strings of unicode characters come out as 'z1234Uz5678U', we
   -- could remove the 'U' in the middle (the 'z' works as a separator).
 
+       showHex = showIntAtBase 16 intToDigit
+       -- needed because prior to GHC 6.2, Numeric.showHex added a "0x" prefix
+
 zDecodeString :: EncodedString -> UserString
 zDecodeString [] = []
 zDecodeString ('Z' : d : rest)