-- so don't mention the IP names
extractHsPredTyNames (HsClassP cls tys)
= unitNameSet cls `unionNameSets` extractHsTyNames_s tys
+extractHsPredTyNames (HsEqualP ty1 ty2)
+ = extractHsTyNames ty1 `unionNameSets` extractHsTyNames ty2
extractHsPredTyNames (HsIParam n ty)
= extractHsTyNames ty
\end{code}