(** *** Comparison of addition with left operand *)

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(** ** Order and opposite                                *)
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(** *** Contravariant compatibility *)
Lemma Ropp_gt_lt_contravar : forall r1 r2, r1 > r2 -> - r1 < - r2.
#[global]
Hint Resolve Ropp_gt_lt_contravar : core.