elim (dec_min (R_cpmuwe h G L T) … Hn) -Hn
[| /2 width=2 by cnv_R_cpmuwe_dec/ ] #n0 #_ -n
elim (ac_dec … Ha n0) -Ha
- [ * #n #Hn #Ha * #X0 #HX0 #_
+ [ * #n #Ha #Hn * #X0 #HX0 #_
elim (abst_dec X0)
[ * #p #W #U0 #H destruct
elim (cnv_cpes_dec … 1 0 … HV W) [ #HVW | #HnVW ]
include "static_2/notation/functions/two_0.ma".
include "static_2/notation/functions/omega_0.ma".
-(* APPLICABILITY CONDITION *************************************************)
+(* APPLICABILITY CONDITION **************************************************)
(* applicability condition specification *)
record ac: Type[0] ≝ {
(* applicability condition postulates *)
record ac_props (a): Prop ≝ {
- ac_dec: ∀m. Decidable (∃∃n. m ≤ n & ad a n)
+ ac_dec: ∀m. Decidable (∃∃n. ad a n & m ≤ n)
}.
(* Notable specifications ***************************************************)
lemma ac_eq_props (k): ac_props (ac_eq k) ≝ mk_ac_props ….
#m elim (le_dec m k) #Hm
[ /3 width=3 by or_introl, ex2_intro/
-| @or_intror * #n #Hmn #H destruct /2 width=1 by/
+| @or_intror * #n #Hn #Hmn destruct /2 width=1 by/
+]
+qed.
+
+definition ac_le (k): ac ≝ mk_ac (λn. n ≤ k).
+
+lemma ac_le_props (k): ac_props (ac_le k) ≝ mk_ac_props ….
+#m elim (le_dec m k) #Hm
+[ /3 width=3 by or_introl, ex2_intro/
+| @or_intror * #n #Hn #Hmn
+ /3 width=3 by transitive_le/
]
qed.
--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||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 "static_2/syntax/ac.ma".
+
+(* APPLICABILITY CONDITION PREORDER *****************************************)
+
+definition acle: relation ac ≝
+ λa1,a2. ∀m. ad a1 m → ∃∃n. ad a2 n & m ≤ n.
+
+interpretation "preorder (applicability domain)"
+ 'subseteq a1 a2 = (acle a1 a2).
+
+(* Basic properties *********************************************************)
+
+lemma acle_refl: reflexive … acle.
+/2 width=3 by ex2_intro/ qed.
+
+lemma acle_omega (a): a ⊆ 𝛚.
+/2 width=1 by acle_refl/
+qed.
+
+lemma acle_one (a): ∀n. ad a n → 𝟏 ⊆ a.
+#a #n #Ha #m #Hm destruct
+/2 width=3 by ex2_intro/
+qed.
+
+lemma acle_eq_monotonic_le (k1) (k2):
+ k1 ≤ k2 → (ac_eq k1) ⊆ (ac_eq k2).
+#k1 #k2 #Hk #m #Hm destruct
+/2 width=3 by ex2_intro/
+qed.
+
+lemma acle_le_monotonic_le (k1) (k2):
+ k1 ≤ k2 → (ac_le k1) ⊆ (ac_le k2).
+#k1 #k2 #Hk #m #Hm
+/3 width=3 by acle_refl, transitive_le/
+qed.
+
+lemma acle_eq_le (k): (ac_eq k) ⊆ (ac_le k).
+#k #m #Hm destruct
+/2 width=1 by acle_refl, le_n/
+qed.
+
+lemma acle_le_eq (k): (ac_le k) ⊆ (ac_eq k).
+#k #m #Hm /2 width=3 by ex2_intro/
+qed.
--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||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 "static_2/syntax/acle.ma".
+
+(* APPLICABILITY CONDITION PREORDER *****************************************)
+
+(* Main properties **********************************************************)
+
+theorem acle_trans: Transitive … acle.
+#a1 #a #Ha1 #a2 #Ha2 #m1 #Hm1
+elim (Ha1 … Hm1) -Ha1 -Hm1 #m #Ha #Hm1
+elim (Ha2 … Ha) -Ha2 -Ha #m2 #Ha2 #Hm2
+/3 width=5 by transitive_le, ex2_intro/
+qed-.
class "red"
[ { "syntax" * } {
[ { "applicability condition" * } {
+ [ [ "preorder" ] "acle" + "( ? ⊆ ? )" "acle_acle" * ]
[ [ "properties" ] "ac" + "( 𝟏 )" + "( 𝟐 )" + "( 𝛚 )" * ]
}
]