update in delayed_updating

[helm.git] / matita / matita / contribs / lambdadelta / delayed_updating / reduction / dbfr_unprotected.ma

diff --git a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dbfr_unprotected.ma b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dbfr_unprotected.ma
new file mode 100644 (file)
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+++ b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dbfr_unprotected.ma
@@ -0,0 +1,42 @@
+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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 "delayed_updating/reduction/ibfr_constructors.ma".
+include "delayed_updating/substitution/lift_prototerm_constructors.ma".
+include "ground/arith/pnat_two.ma".
+
+(* DELAYED BALANCED FOCUSED REDUCTION ***************************************)
+
+(* Example of unprotected balanced β-reduction ******************************)
+
+definition l3_t0: prototerm ≝
+           (𝛌.＠(⧣𝟏).＠(𝛌.＠(⧣𝟐).⧣𝟏).𝛌.⧣𝟏).
+
+definition l3_t1: prototerm ≝
+           (𝛌.＠(⧣𝟏).＠(𝛌.＠(⧣𝟐).⧣𝟏).𝛌.(𝛌.＠(⧣↑𝟐).⧣𝟏)).
+
+lemma l3_t01:
+      l3_t0 ➡𝐢𝐛𝐟[𝗟◗𝗔◗𝗔◗𝗟◗𝐞] l3_t1.
+@ibfr_abst_hd
+@ibfr_appl_hd
+@ibfr_eq_trans [| @ibfr_beta_0 // ]
+@appl_eq_repl [ // ]
+@abst_eq_repl
+@(subset_eq_canc_sn … (fsubst_empty_rc …))
+@(subset_eq_canc_sn … (lift_term_abst …))
+@abst_eq_repl
+@(subset_eq_canc_sn … (lift_term_appl … ))
+@appl_eq_repl
+@(subset_eq_canc_sn … (lift_term_oref_pap … )) //
+qed.