Open Scope Z_scope.
(* Pierre L: examples gathered while debugging romega. *)
(* Starting from Coq 8.9 (late 2018), `romega` tactics are deprecated. The tests in this file remain but now call the `lia` tactic. *)

Lemma test_lia_4 : forall hr ha,
ha = 0 ->
(ha = 0 -> hr =0) ->
hr = 0.