proposition: Lemma H5draw_win_win ht i l : Hiv (i :: l) -> ht_valid ht -> f1 i = win -> f2 edraw ewin ht i = ewin :> estate.
proof: Proof. by move/Hiv_hd=> [] _ [_ H _ _] _; apply: H. Qed.
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(all_algebra)