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7 (* ||T|| The HELM team. *)
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15 set "baseuri" "cic:/matita/test/".
17 include "logic/connectives.ma".
18 include "logic/equality.ma".
22 lemma step : ∀a:T.∀H:a=a. eq_ind T a (λx.a = x) H a (sym_eq ? ? ? H) = refl_eq T a.
23 intros (a H). cases H. reflexivity.
26 inductive eq4 (A : Type) (x : A) (y : A) : A → A → Prop ≝
27 eq_refl4 : eq4 A x y x y.
29 lemma step4 : ∀a,b:T.∀H:eq4 T a b a b.
30 eq4_ind T a b (λx,y.eq4 T x y a b) H a b H = eq_refl4 T a b.
31 intros (a b H). cases H. reflexivity.