instance Ord name => Eq (HsDecl name pat) where
-- Used only when comparing interfaces,
-- at which time only signature and type/class decls
- (SigD s1) == (SigD s2) = s1 == s2
+ (SigD s1) == (SigD s2) = s1 == s2
(TyClD d1) == (TyClD d2) = d1 == d2
+ _ == _ = False
\end{code}