X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FdeSugar%2FDsBinds.lhs;h=39e7e298abaf37d70c8e25fdaac2198e3fc95493;hp=85883dc05fadf427228d9de08fae229a120e58d1;hb=d9a655dad8e013e41c74dca98fb86c4ed6f29879;hpb=fdf8656855d26105ff36bdd24d41827b05037b91

diff --git a/compiler/deSugar/DsBinds.lhs b/compiler/deSugar/DsBinds.lhs
index 85883dc..39e7e29 100644
--- a/compiler/deSugar/DsBinds.lhs
+++ b/compiler/deSugar/DsBinds.lhs
@@ -493,6 +493,15 @@ dsSpec :: Maybe CoreExpr  	-- Just rhs => RULE is for a local binding
        -> Located TcSpecPrag
        -> DsM (Maybe (OrdList (Id,CoreExpr), CoreRule))
 dsSpec mb_poly_rhs (L loc (SpecPrag poly_id spec_co spec_inl))
+  | isJust (isClassOpId_maybe poly_id)
+  = putSrcSpanDs loc $ 
+    do { warnDs (ptext (sLit "Ignoring useless SPECIALISE pragma for class method selector") 
+                 <+> quotes (ppr poly_id))
+       ; return Nothing  }  -- There is no point in trying to specialise a class op
+       	 		    -- Moreover, classops don't (currently) have an inl_sat arity set
+			    -- (it would be Just 0) and that in turn makes makeCorePair bleat
+
+  | otherwise
   = putSrcSpanDs loc $ 
     do { let poly_name = idName poly_id
        ; spec_name <- newLocalName poly_name
@@ -598,13 +607,13 @@ decomposeRuleLhs bndrs lhs
 
    bad_shape_msg = hang (ptext (sLit "RULE left-hand side too complicated to desugar"))
                       2 (ppr opt_lhs)
-   dead_msg bndr = hang (ptext (sLit "Forall'd") <+> pp_bndr bndr
-				 <+> ptext (sLit "is not bound in RULE lhs"))
+   dead_msg bndr = hang (sep [ ptext (sLit "Forall'd") <+> pp_bndr bndr
+			     , ptext (sLit "is not bound in RULE lhs")])
                       2 (ppr opt_lhs)
    pp_bndr bndr
-    | isTyVar bndr  = ptext (sLit "type variable") <+> ppr bndr
-    | isEvVar bndr  = ptext (sLit "constraint") <+> ppr bndr <+> dcolon <+> ppr (evVarPred bndr)
-    | otherwise     = ptext (sLit "variable") <+> ppr bndr
+    | isTyVar bndr  = ptext (sLit "type variable") <+> quotes (ppr bndr)
+    | isEvVar bndr  = ptext (sLit "constraint") <+> quotes (ppr (evVarPred bndr))
+    | otherwise     = ptext (sLit "variable") <+> quotes (ppr bndr)
 \end{code}
 
 Note [Simplifying the left-hand side of a RULE]