Global Instance valid_rnd_NA : Valid_rnd (Znearest (Zle_bool 0)) := valid_rnd_N _.

Theorem generic_inclusion_le_ge : forall e1 e2, (e1 < e2)%Z -> ( forall e, (e1 < e <= e2)%Z -> (fexp2 e <= fexp1 e)%Z ) -> forall x, (bpow e1 <= Rabs x <= bpow e2)%R -> generic_format fexp1 x -> generic_format fexp2 x.