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substVect :: Subst -> CoreVect -> CoreVect
-substVect _subst (Vect v Nothing) = Vect v Nothing
-substVect subst (Vect v (Just rhs)) = Vect v (Just (simpleOptExprWith subst rhs))
+substVect _subst (Vect v Nothing) = Vect v Nothing
+substVect subst (Vect v (Just rhs)) = Vect v (Just (simpleOptExprWith subst rhs))
+substVect _subst (NoVect v) = NoVect v
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substVarSet :: Subst -> VarSet -> VarSet