- we introduce recursive free variables of a term in a context ...

- some symbols added

diff --git a/matita/matita/contribs/lambdadelta/basic_2/notation/relations/cofreestar_3.ma b/matita/matita/contribs/lambdadelta/basic_2/notation/relations/cofreestar_3.ma
new file mode 100644 (file)
index 0000000..86fc1f1
--- /dev/null
+++ b/matita/matita/contribs/lambdadelta/basic_2/notation/relations/cofreestar_3.ma
@@ -0,0 +1,19 @@
+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+(* NOTATION FOR THE FORMAL SYSTEM λδ ****************************************)
+
+notation "hvbox( d ~ ϵ break 𝐅 * ⦃ term 46 L, break term 46 T ⦄ )"
+   non associative with precedence 45
+   for @{ 'CoFreeStar $d $L $T }.

diff --git a/matita/matita/contribs/lambdadelta/basic_2/substitution/cofrees.ma b/matita/matita/contribs/lambdadelta/basic_2/substitution/cofrees.ma
new file mode 100644 (file)
index 0000000..daab997
--- /dev/null
+++ b/matita/matita/contribs/lambdadelta/basic_2/substitution/cofrees.ma
@@ -0,0 +1,34 @@
+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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/notation/relations/cofreestar_3.ma".
+include "basic_2/substitution/cpys.ma".
+
+(* CONTEXT-SENSITIVE EXCLUSION FROM FREE VARIABLES **************************)
+
+definition cofrees: relation3 nat lenv term ≝
+                    λd,L,U1. ∀U2. ⦃⋆, L⦄ ⊢ U1 ▶*[d, ∞] U2 → ∃T2. ⇧[d, 1] T2 ≡ U2.
+
+interpretation
+   "context-sensitive exclusion from free variables (term)"
+   'CoFreeStar d L T = (cofrees d L T).
+
+(* Basic forward lemmas *****************************************************)
+
+lemma cofrees_fwd_lift: ∀L,U,d. d ~ϵ 𝐅*⦃L, U⦄ → ∃T. ⇧[d, 1] T ≡ U.
+/2 width=1 by/ qed-.
+
+lemma nlift_frees: ∀L,U,d. (∀T. ⇧[d, 1] T ≡ U → ⊥) → (d ~ϵ 𝐅*⦃L, U⦄ → ⊥).
+#L #U #d #HnTU #H elim (cofrees_fwd_lift … H) -H /2 width=2 by/
+qed-.

diff --git a/matita/matita/predefined_virtuals.ml b/matita/matita/predefined_virtuals.ml
index 6311d5933360db0a5a0fbbca0a238bb40b41be43..0a1135cb4bdc92f05e5a416698c0d5373c4a5167 100644 (file)
--- a/matita/matita/predefined_virtuals.ml
+++ b/matita/matita/predefined_virtuals.ml
@@ -1518,7 +1518,7 @@ let predefined_classes = [
  ["⇑"; "⇧"; "⬆"; ] ; 
  ["⇓"; "⇩"; "⬇"; "⬊"; "➷"; ] ;
  ["↔"; "⇔"; "⬄"; "⬌"; ] ; 
- ["≤"; "≲"; "≼"; "≰"; "≴"; "⋠"; "⊑"; ];
+ ["â\89¤"; "â\89²"; "â\89¼"; "â\89°"; "â\89´"; "â\8b "; "â\8a\86"; "â«\83"; "â\8a\91"; ];
  ["_"; "↓"; "↙"; "⎽"; "⎼"; "⎻"; "⎺"; ];
  ["<"; "≺"; "≮"; "⊀"; "〈"; "«"; "❬"; "❮"; "❰"; ] ;
  ["("; "❨"; "❪"; "❲"; "（"; ];
@@ -1529,7 +1529,7 @@ let predefined_classes = [
  ["}"; "❵"; "⦄" ] ;
  ["□"; "◽"; "▪"; "◾"; ];
  ["◊"; "♢"; "⧫"; "♦"; "⟐"; "⟠"; ] ;
- [">"; "⭃"; "⧁"; "〉"; "»"; "❭"; "❯"; "❱"; "▸"; "►"; "▶"; ] ;
+ [">"; "⭃"; "⧁"; "〉"; "»"; "❭"; "❯"; "❱"; "▸"; "►"; "▶"; "⊃"; "⊐"; ] ;
  ["≥"; "⪀"; "≽"; "⪴"; "⥸"; "⊒"; ]; 
  ["∨"; "⩖"; "⋓"; ] ;
  ["a"; "α"; "𝕒"; "𝐚"; "𝛂"; "ⓐ"; ] ;