- dependences on ceq and ceq_ext fixed

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / syntax / ceq_ext.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/syntax/ceq_ext.ma b/matita/matita/contribs/lambdadelta/basic_2/syntax/ceq_ext.ma
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+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||M||                                                             *)
+(*      ||A||       A project by Andrea Asperti                           *)
+(*      ||T||                                                             *)
+(*      ||I||       Developers:                                           *)
+(*      ||T||         The HELM team.                                      *)
+(*      ||A||         http://helm.cs.unibo.it                             *)
+(*      \   /                                                             *)
+(*       \ /        This file is distributed under the terms of the       *)
+(*        v         GNU General Public License Version 2                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+include "basic_2/syntax/cext2.ma".
+
+(* CONTEXT-AWARE SYNTACTIC EQUIVALENCE FOR BINDERS **************************)
+
+definition ceq_ext: lenv → relation bind ≝
+                    cext2 ceq.
+
+(* Basic properties *********************************************************)
+
+lemma ceq_ext_refl (L): reflexive … (ceq_ext L).
+/2 width=1 by ext2_refl/ qed.
+
+(* Basic inversion lemmas ***************************************************)
+
+lemma ceq_ext_inv_eq: ∀L,I1,I2. ceq_ext L I1 I2 → I1 = I2.
+#L #I1 #I2 * -I1 -I2 //
+qed-.