[project @ 2000-11-08 14:52:06 by simonpj]

[ghc-hetmet.git] / ghc / compiler / typecheck / TcGenDeriv.lhs

diff --git a/ghc/compiler/typecheck/TcGenDeriv.lhs b/ghc/compiler/typecheck/TcGenDeriv.lhs
index 670db8e..41e366e 100644 (file)
--- a/ghc/compiler/typecheck/TcGenDeriv.lhs
+++ b/ghc/compiler/typecheck/TcGenDeriv.lhs
@@ -63,7 +63,7 @@ import Panic          ( panic, assertPanic )
 import Maybes          ( maybeToBool )
 import Constants
 import List            ( partition, intersperse )
-import Outputable      ( pprPanic, ppr )
+import Outputable      ( pprPanic, ppr, pprTrace )
 
 #if __GLASGOW_HASKELL__ >= 404
 import GlaExts         ( fromInt )
@@ -914,8 +914,8 @@ gen_Read_binds get_fixity tycon
              c.f. Figure 18 in Haskell 1.1 report.
            -}
           paren_prec_limit
-            | not is_infix  = fromInt maxPrecedence
-            | otherwise     = getFixity get_fixity dc_nm
+            | not is_infix  = defaultPrecedence
+            | otherwise     = getPrecedence get_fixity dc_nm
 
           read_paren_arg   -- parens depend on precedence...
            | nullary_con  = false_Expr -- it's optional.
@@ -1027,8 +1027,8 @@ gen_Show_binds get_fixity tycon
                c.f. Figure 16 and 17 in Haskell 1.1 report
              -}  
             paren_prec_limit
-               | not is_infix = fromInt maxPrecedence + 1
-               | otherwise    = getFixity get_fixity dc_nm + 1
+               | not is_infix = defaultPrecedence + 1
+               | otherwise    = getPrecedence get_fixity dc_nm + 1
 
 \end{code}
 
@@ -1041,24 +1041,26 @@ getLRPrecs is_infix get_fixity nm = [lp, rp]
        cf. Figures 16-18 in Haskell 1.1 report.
      -}
      (con_left_assoc, con_right_assoc) = isLRAssoc get_fixity nm
-     paren_con_prec = getFixity get_fixity nm
-     maxPrec       = fromInt maxPrecedence
+     paren_con_prec = getPrecedence get_fixity nm
 
      lp
-      | not is_infix   = maxPrec + 1
+      | not is_infix   = defaultPrecedence + 1
       | con_left_assoc = paren_con_prec
       | otherwise      = paren_con_prec + 1
                  
      rp
-      | not is_infix    = maxPrec + 1
+      | not is_infix    = defaultPrecedence + 1
       | con_right_assoc = paren_con_prec
       | otherwise       = paren_con_prec + 1
                  
-getFixity :: (Name -> Maybe Fixity) -> Name -> Integer
-getFixity get_fixity nm 
+defaultPrecedence :: Integer
+defaultPrecedence = fromInt maxPrecedence
+
+getPrecedence :: (Name -> Maybe Fixity) -> Name -> Integer
+getPrecedence get_fixity nm 
    = case get_fixity nm of
         Just (Fixity x _) -> fromInt x
-        other            -> pprPanic "TcGenDeriv.getFixity" (ppr nm)
+        other            -> pprTrace "TcGenDeriv.getPrecedence" (ppr nm) defaultPrecedence
 
 isLRAssoc :: (Name -> Maybe Fixity) -> Name -> (Bool, Bool)
 isLRAssoc get_fixity nm =