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ruleDeclFVs (HsRule _ _ _ _ _ _) = emptyFVs
-ruleDeclFVs (IfaceRule _ vars _ _ rhs _)
+ruleDeclFVs (IfaceRule _ vars _ args rhs _)
= delFVs (map ufBinderName vars) $
- ufExprFVs rhs
+ ufExprFVs rhs `plusFV` plusFVs (map ufExprFVs args)
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conDeclFVs (ConDecl _ _ tyvars context details _)