From 538c84b5b1129b34c051c364fdd304f52714482c Mon Sep 17 00:00:00 2001
From: Ferruccio Guidi <ferruccio.guidi@unibo.it>
Date: Mon, 31 Jan 2022 22:50:04 +0100
Subject: [PATCH] update in ground

+ additions to subsets
---
 .../ground/lib/subset_ext_equivalence.ma      | 10 ++++++++++
 .../ground/lib/subset_ext_inclusion.ma        | 19 +++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_equivalence.ma b/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_equivalence.ma
index f20aca24f..28e4facc8 100644
--- a/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_equivalence.ma
+++ b/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_equivalence.ma
@@ -19,8 +19,18 @@ include "ground/lib/subset_equivalence.ma".
 
 (* Constructions with subset_equivalence ************************************)
 
+lemma subset_equivalence_ext_f1_exteq (A1) (A0) (f1) (f2) (u):
+      f1 ⊜ f2 → subset_ext_f1 A1 A0 f1 u ⇔ subset_ext_f1 A1 A0 f2 u.
+/3 width=3 by subset_inclusion_ext_f1_exteq, conj/
+qed.
+
 lemma subset_equivalence_ext_f1_bi (A1) (A0) (f) (u1) (v1):
       u1 ⇔ v1 → subset_ext_f1 A1 A0 f u1 ⇔ subset_ext_f1 A1 A0 f v1.
 #A1 #A0 #f #u1 #v1 * #Huv1 #Hvu1
 /3 width=3 by subset_inclusion_ext_f1_bi, conj/
 qed.
+
+lemma subset_inclusion_ext_f1_compose (A0) (A1) (A2) (f1) (f2) (u):
+      subset_ext_f1 A1 A2 f2 (subset_ext_f1 A0 A1 f1 u) ⇔ subset_ext_f1 A0 A2 (f2∘f1) u.
+/3 width=1 by subset_inclusion_ext_f1_compose_dx, subset_inclusion_ext_f1_compose_sn, conj/
+qed.
diff --git a/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_inclusion.ma b/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_inclusion.ma
index 7fd5fd418..f16fc373a 100644
--- a/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_inclusion.ma
+++ b/matita/matita/contribs/lambdadelta/ground/lib/subset_ext_inclusion.ma
@@ -14,17 +14,36 @@
 
 include "ground/lib/subset_inclusion.ma".
 include "ground/lib/subset_ext.ma".
+include "ground/lib/exteq.ma".
 
 (* EXTENSIONS FOR SUBSETS ***************************************************)
 
 (* Constructions with subset_inclusion **************************************)
 
+lemma subset_inclusion_ext_f1_exteq (A1) (A0) (f1) (f2) (u):
+      f1 ⊜ f2 → subset_ext_f1 A1 A0 f1 u ⊆ subset_ext_f1 A1 A0 f2 u.
+#A1 #A0 #f1 #f2 #u #Hf #a0 * #a1 #Hau1 #H destruct
+/2 width=1 by subset_in_ext_f1_dx/
+qed.
+
 lemma subset_inclusion_ext_f1_bi (A1) (A0) (f) (u1) (v1):
       u1 ⊆ v1 → subset_ext_f1 A1 A0 f u1 ⊆ subset_ext_f1 A1 A0 f v1.
 #A1 #A0 #f #u1 #v1 #Huv1 #a0 * #a1 #Hau1 #H destruct
 /3 width=3 by subset_in_ext_f1_dx/
 qed.
 
+lemma subset_inclusion_ext_f1_compose_sn (A0) (A1) (A2) (f1) (f2) (u):
+      subset_ext_f1 A1 A2 f2 (subset_ext_f1 A0 A1 f1 u) ⊆ subset_ext_f1 A0 A2 (f2∘f1) u.
+#A0 #A1 #A2 #f1 #f2 #u #a2 * #a1 * #a0 #Ha0 #H1 #H2 destruct
+/2 width=1 by subset_in_ext_f1_dx/
+qed.
+
+lemma subset_inclusion_ext_f1_compose_dx (A0) (A1) (A2) (f1) (f2) (u):
+      subset_ext_f1 A0 A2 (f2∘f1) u ⊆ subset_ext_f1 A1 A2 f2 (subset_ext_f1 A0 A1 f1 u).
+#A0 #A1 #A2 #f1 #f2 #u #a2 * #a0 #Ha0 #H0 destruct
+/3 width=1 by subset_in_ext_f1_dx/
+qed.
+
 lemma subset_inclusion_ext_p1_trans (A1) (Q) (u1) (v1):
       u1 ⊆ v1 → subset_ext_p1 A1 Q v1 → subset_ext_p1 A1 Q u1.
 #A1 #Q #u1 #v1 #Huv1 #Hv1
-- 
2.39.2