(*
-\ 5h1\ 6Equivalence\ 5/h1\ 6*)
+\ 5h1\ 6Regular Expressions Equivalence\ 5/h1\ 6*)
include "tutorial/chapter9.ma".
-(* We say that two pres \langle i_1,b_1\rangle$ and
-$\langle i_1,b_1\rangle$ are {\em cofinal} if and only if
-$b_1 = b_2$. *)
+(* We say that two pres 〈i_1,b_1〉 and 〈i_1,b_1〉 are {\em cofinal} if and
+only if b_1 = b_2. *)
definition cofinal ≝ λS.λp:(\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S)\ 5a title="Product" href="cic:/fakeuri.def(1)"\ 6×\ 5/a\ 6(\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S).
\ 5a title="pair pi2" href="cic:/fakeuri.def(1)"\ 6\snd\ 5/a\ 6 (\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 p) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a title="pair pi2" href="cic:/fakeuri.def(1)"\ 6\snd\ 5/a\ 6 (\ 5a title="pair pi2" href="cic:/fakeuri.def(1)"\ 6\snd\ 5/a\ 6 p).
lemma occ_enough: ∀S.∀e1,e2:\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.
(∀w.(\ 5a href="cic:/matita/tutorial/chapter5/sublist.def(5)"\ 6sublist\ 5/a\ 6 S w (\ 5a href="cic:/matita/tutorial/chapter10/occ.def(7)"\ 6occ\ 5/a\ 6 S e1 e2))→ \ 5a href="cic:/matita/tutorial/chapter10/cofinal.def(2)"\ 6cofinal\ 5/a\ 6 ? \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 ? w e1,\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 ? w e2〉)
- →∀w.\ 5a href="cic:/matita/tutorial/chapter10/cofinal.def(2)"\ 6cofinal\ 5/a\ 6 ? \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 ? w e1,\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 ? w e2〉.
+ →∀w.\ 5a href="cic:/matita/tutorial/chapter10/cofinal.def(2)"\ 6cofinal\ 5/a\ 6 ? \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 ? w e1,\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 ? w e2〉.
#S #e1 #e2 #H #w
cases (\ 5a href="cic:/matita/tutorial/chapter5/decidable_sublist.def(6)"\ 6decidable_sublist\ 5/a\ 6 S w (\ 5a href="cic:/matita/tutorial/chapter10/occ.def(7)"\ 6occ\ 5/a\ 6 S e1 e2)) [@H] -H #H
>\ 5a href="cic:/matita/tutorial/chapter9/to_pit.def(10)"\ 6to_pit\ 5/a\ 6 [2: @(\ 5a href="cic:/matita/basics/logic/not_to_not.def(3)"\ 6not_to_not\ 5/a\ 6 … H) #H1 #a #memba @\ 5a href="cic:/matita/tutorial/chapter5/sublist_unique_append_l1.def(6)"\ 6sublist_unique_append_l1\ 5/a\ 6 @H1 //]
(* Using lemma equiv_sem_occ it is easy to prove the following result: *)
lemma bisim_to_sem: ∀S:\ 5a href="cic:/matita/tutorial/chapter4/DeqSet.ind(1,0,0)"\ 6DeqSet\ 5/a\ 6.∀l:\ 5a href="cic:/matita/basics/list/list.ind(1,0,1)"\ 6list\ 5/a\ 6 ?.∀e1,e2: \ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.
- \ 5a href="cic:/matita/tutorial/chapter10/is_bisim.def(8)"\ 6is_bisim\ 5/a\ 6 S l (\ 5a href="cic:/matita/tutorial/chapter10/occ.def(7)"\ 6occ\ 5/a\ 6 S e1 e2) → \ 5a href="cic:/matita/tutorial/chapter5/memb.fix(0,2,4)"\ 6memb\ 5/a\ 6 ? \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉 l \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6 → \ 5a title="in_prl" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e1}\ 5a title="extensional equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 61\ 5a title="in_prl" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e2}.
+ \ 5a href="cic:/matita/tutorial/chapter10/is_bisim.def(8)"\ 6is_bisim\ 5/a\ 6 S l (\ 5a href="cic:/matita/tutorial/chapter10/occ.def(7)"\ 6occ\ 5/a\ 6 S e1 e2) → \ 5a href="cic:/matita/tutorial/chapter5/memb.fix(0,2,4)"\ 6memb\ 5/a\ 6 ?\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉 l \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6 → \ 5a title="in_prl" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e1}\ 5a title="extensional equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 61\ 5a title="in_prl" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e2}.
#S #l #e1 #e2 #Hbisim #Hmemb @\ 5a href="cic:/matita/tutorial/chapter10/equiv_sem_occ.def(17)"\ 6equiv_sem_occ\ 5/a\ 6
-#w #Hsub @(\ 5a href="cic:/matita/basics/logic/proj1.def(2)"\ 6proj1\ 5/a\ 6 … (Hbisim \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 S w e1,\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 S w e2〉 ?))
+#w #Hsub @(\ 5a href="cic:/matita/basics/logic/proj1.def(2)"\ 6proj1\ 5/a\ 6 … (Hbisim \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 S w e1,\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 S w e2〉 ?))
lapply Hsub @(\ 5a href="cic:/matita/basics/list/list_elim_left.def(10)"\ 6list_elim_left\ 5/a\ 6 … w) [//]
#a #w1 #Hind #Hsub >\ 5a href="cic:/matita/tutorial/chapter9/moves_left.def(9)"\ 6moves_left\ 5/a\ 6 >\ 5a href="cic:/matita/tutorial/chapter9/moves_left.def(9)"\ 6moves_left\ 5/a\ 6 @(\ 5a href="cic:/matita/basics/logic/proj2.def(2)"\ 6proj2\ 5/a\ 6 …(Hbisim …(Hind ?)))
[#x #Hx @Hsub @\ 5a href="cic:/matita/tutorial/chapter5/memb_append_l1.def(5)"\ 6memb_append_l1\ 5/a\ 6 //
let rec pitem_enum S (i:\ 5a href="cic:/matita/tutorial/chapter7/re.ind(1,0,1)"\ 6re\ 5/a\ 6 S) on i ≝
match i with
- [ z ⇒ (\ 5a href="cic:/matita/tutorial/chapter7/pitem.con(0,1,1)"\ 6pz\ 5/a\ 6\ 5span class="error" title="Parse error: SYMBOL ':' or RPAREN expected after [term] (in [term])"\ 6\ 5/span\ 6\ 5span class="error" title="Parse error: SYMBOL ':' or RPAREN expected after [term] (in [term])"\ 6\ 5/span\ 6 S)\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]
+ [ z ⇒ (\ 5a href="cic:/matita/tutorial/chapter7/pitem.con(0,1,1)"\ 6pz\ 5/a\ 6 S)\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]
| e ⇒ (\ 5a href="cic:/matita/tutorial/chapter7/pitem.con(0,2,1)"\ 6pe\ 5/a\ 6 S)\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]
| s y ⇒ (\ 5a href="cic:/matita/tutorial/chapter7/pitem.con(0,3,1)"\ 6ps\ 5/a\ 6 S y)\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:(\ 5a href="cic:/matita/tutorial/chapter7/pitem.con(0,4,1)"\ 6pp\ 5/a\ 6 S y)\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]
| o i1 i2 ⇒ \ 5a href="cic:/matita/basics/list/compose.def(2)"\ 6compose\ 5/a\ 6 ??? (\ 5a href="cic:/matita/tutorial/chapter7/pitem.con(0,6,1)"\ 6po\ 5/a\ 6 S) (pitem_enum S i1) (pitem_enum S i2)
qed.
definition pre_enum ≝ λS.λi:\ 5a href="cic:/matita/tutorial/chapter7/re.ind(1,0,1)"\ 6re\ 5/a\ 6 S.
- \ 5a href="cic:/matita/basics/list/compose.def(2)"\ 6compose\ 5/a\ 6 ??? (λi,b.\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6i,b〉) (\ 5a href="cic:/matita/tutorial/chapter10/pitem_enum.fix(0,1,3)"\ 6pitem_enum\ 5/a\ 6 S i) \ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6\ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6;\ 5a href="cic:/matita/basics/bool/bool.con(0,2,0)"\ 6false\ 5/a\ 6].
+ \ 5a href="cic:/matita/basics/list/compose.def(2)"\ 6compose\ 5/a\ 6 ??? (λi,b.\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6i,b〉) ( \ 5a href="cic:/matita/tutorial/chapter10/pitem_enum.fix(0,1,3)"\ 6pitem_enum\ 5/a\ 6 S i) (\ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a href="cic:/matita/basics/bool/bool.con(0,2,0)"\ 6false\ 5/a\ 6\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]).
lemma pre_enum_complete : ∀S.∀e:\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.
\ 5a href="cic:/matita/tutorial/chapter5/memb.fix(0,2,4)"\ 6memb\ 5/a\ 6 ? e (\ 5a href="cic:/matita/tutorial/chapter10/pre_enum.def(4)"\ 6pre_enum\ 5/a\ 6 S (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e|)) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6.
// cases b normalize //
qed.
-definition space_enum ≝ λS.λi1,i2:\ 5a href="cic:/matita/tutorial/chapter7/re.ind(1,0,1)"\ 6re\ 5/a\ 6 S.
- \ 5a href="cic:/matita/basics/list/compose.def(2)"\ 6compose\ 5/a\ 6 ??? (λe1,e2.\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉) (\ 5a href="cic:/matita/tutorial/chapter10/pre_enum.def(4)"\ 6pre_enum\ 5/a\ 6 S i1) (\ 5a href="cic:/matita/tutorial/chapter10/pre_enum.def(4)"\ 6pre_enum\ 5/a\ 6 S i2).
+definition space_enum ≝ λS.λi1,i2: \ 5a href="cic:/matita/tutorial/chapter7/re.ind(1,0,1)"\ 6re\ 5/a\ 6 S.
+ \ 5a href="cic:/matita/basics/list/compose.def(2)"\ 6compose\ 5/a\ 6 ??? (λe1,e2.\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉) ( \ 5a href="cic:/matita/tutorial/chapter10/pre_enum.def(4)"\ 6pre_enum\ 5/a\ 6 S i1) (\ 5a href="cic:/matita/tutorial/chapter10/pre_enum.def(4)"\ 6pre_enum\ 5/a\ 6 S i2).
lemma space_enum_complete : ∀S.∀e1,e2: \ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.
- \ 5a href="cic:/matita/tutorial/chapter5/memb.fix(0,2,4)"\ 6memb\ 5/a\ 6 ? \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉 (\ 5a href="cic:/matita/tutorial/chapter10/space_enum.def(5)"\ 6space_enum\ 5/a\ 6 S (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e1|) (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e2|)) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6.
+ \ 5a href="cic:/matita/tutorial/chapter5/memb.fix(0,2,4)"\ 6memb\ 5/a\ 6 ? \ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉 ( \ 5a href="cic:/matita/tutorial/chapter10/space_enum.def(5)"\ 6space_enum\ 5/a\ 6 S (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e1|) (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e2|)) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6.
#S #e1 #e2 @(\ 5a href="cic:/matita/tutorial/chapter5/memb_compose.def(6)"\ 6memb_compose\ 5/a\ 6 … (λi,b.\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6i,b〉))
// qed.
-definition all_reachable ≝ λS.λe1,e2:\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.λl: \ 5a href="cic:/matita/basics/list/list.ind(1,0,1)"\ 6list\ 5/a\ 6 ?.
+definition all_reachable ≝ λS.λe1,e2: \ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.λl: \ 5a href="cic:/matita/basics/list/list.ind(1,0,1)"\ 6list\ 5/a\ 6 ?.
\ 5a href="cic:/matita/tutorial/chapter5/uniqueb.fix(0,1,5)"\ 6uniqueb\ 5/a\ 6 ? l \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6 \ 5a title="logical and" href="cic:/fakeuri.def(1)"\ 6∧\ 5/a\ 6
∀p. \ 5a href="cic:/matita/tutorial/chapter5/memb.fix(0,2,4)"\ 6memb\ 5/a\ 6 ? p l \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6 →
\ 5a title="exists" href="cic:/fakeuri.def(1)"\ 6∃\ 5/a\ 6w.(\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 S w e1 \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 p) \ 5a title="logical and" href="cic:/fakeuri.def(1)"\ 6∧\ 5/a\ 6 (\ 5a href="cic:/matita/tutorial/chapter9/moves.fix(0,1,7)"\ 6moves\ 5/a\ 6 S w e2 \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a title="pair pi2" href="cic:/fakeuri.def(1)"\ 6\snd\ 5/a\ 6 p).
(* We are ready to prove that bisim is correct; we use the invariant
that at each call of bisim the two lists visited and frontier only contain
-nodes reachable from \langle e_1,e_2\rangle, hence it is absurd to suppose
-to meet a pair which is not cofinal. *)
+nodes reachable from 〈e_1,e_2〉, hence it is absurd to suppose to meet a pair
+which is not cofinal. *)
lemma bisim_correct: ∀S.∀e1,e2:\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S.\ 5a title="in_prl" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e1}\ 5a title="extensional equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 61\ 5a title="in_prl" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e2} →
∀l,n.∀frontier,visited:\ 5a href="cic:/matita/basics/list/list.ind(1,0,1)"\ 6list\ 5/a\ 6 ((\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S)\ 5a title="Product" href="cic:/fakeuri.def(1)"\ 6×\ 5/a\ 6(\ 5a href="cic:/matita/tutorial/chapter7/pre.def(1)"\ 6pre\ 5/a\ 6 S)).
|#p1 #H (cases (\ 5a href="cic:/matita/basics/bool/orb_true_l.def(2)"\ 6orb_true_l\ 5/a\ 6 … H)) [#eqp >(\P eqp) // |@r_visited]
]
|whd % [@\ 5a href="cic:/matita/tutorial/chapter5/unique_append_unique.def(6)"\ 6unique_append_unique\ 5/a\ 6 @(\ 5a href="cic:/matita/basics/bool/andb_true_r.def(4)"\ 6andb_true_r\ 5/a\ 6 … u_frontier)]
- @\ 5a href="cic:/matita/tutorial/chapter5/unique_append_elim.dec"\ 6unique_append_elim\ 5/a\ 6 #q #H
+ @\ 5a href="cic:/matita/tutorial/chapter5/unique_append_elim.def(7)"\ 6unique_append_elim\ 5/a\ 6 #q #H
[cases (\ 5a href="cic:/matita/tutorial/chapter10/memb_sons.def(8)"\ 6memb_sons\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter5/memb_filter_memb.def(5)"\ 6memb_filter_memb\ 5/a\ 6 … H)) -H
- #a * #m1 #m2 cases rp #w1 * #mw1 #mw2 @(\ 5a href="cic:/matita/basics/logic/ex.con(0,1,2)"\ 6ex_intro\ 5/a\ 6 … (w1\ 5a title="append" href="cic:/fakeuri.def(1)"\ 6@\ 5/a\ 6\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6a]))
+ #a * #m1 #m2 cases rp #w1 * #mw1 #mw2 @(\ 5a href="cic:/matita/basics/logic/ex.con(0,1,2)"\ 6ex_intro\ 5/a\ 6 … (w1\ 5a title="append" href="cic:/fakeuri.def(1)"\ 6@\ 5/a\ 6(a\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6])))
>\ 5a href="cic:/matita/tutorial/chapter9/moves_left.def(9)"\ 6moves_left\ 5/a\ 6 >\ 5a href="cic:/matita/tutorial/chapter9/moves_left.def(9)"\ 6moves_left\ 5/a\ 6 >mw1 >mw2 >m1 >m2 % //
|@r_frontier @\ 5a href="cic:/matita/tutorial/chapter5/memb_cons.def(5)"\ 6memb_cons\ 5/a\ 6 //
]
- |@\ 5a href="cic:/matita/tutorial/chapter5/unique_append_elim.dec"\ 6unique_append_elim\ 5/a\ 6 #q #H
- [@\ 5a href="cic:/matita/basics/bool/injective_notb.def(4)"\ 6injective_notb\ 5/a\ 6 @(\ 5a href="cic:/matita/tutorial/chapter5/filter_true.def(5)"\ 6filter_true\ 5/a\ 6 … H)
+ |@\ 5a href="cic:/matita/tutorial/chapter5/unique_append_elim.def(7)"\ 6unique_append_elim\ 5/a\ 6 #q #H
+ [@\ 5a href="cic:/matita/basics/bool/injective_notb.def(4)"\ 6injective_notb\ 5/a\ 6 @(\ 5a href="cic:/matita/tutorial/chapter5/memb_filter_true.def(5)"\ 6memb_filter_true\ 5/a\ 6 … H)
|cut ((q\ 5a title="eqb" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6=p) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,2,0)"\ 6false\ 5/a\ 6)
[|#Hpq whd in ⊢ (??%?); >Hpq @disjoint @\ 5a href="cic:/matita/tutorial/chapter5/memb_cons.def(5)"\ 6memb_cons\ 5/a\ 6 //]
cases (\ 5a href="cic:/matita/basics/bool/andb_true.def(5)"\ 6andb_true\ 5/a\ 6 … u_frontier) #notp #_ @(\bf ?)
]
]
qed.
-
+
(* For completeness, we use the invariant that all the nodes in visited are cofinal,
and the sons of visited are either in visited or in the frontier; since
at the end frontier is empty, visited is hence a bisimulation. *)
let e2 ≝ \ 5a title="eclose" href="cic:/fakeuri.def(1)"\ 6•\ 5/a\ 6(\ 5a href="cic:/matita/tutorial/chapter8/blank.fix(0,1,3)"\ 6blank\ 5/a\ 6 ? re2) in
let n ≝ \ 5a href="cic:/matita/arithmetics/nat/nat.con(0,2,0)"\ 6S\ 5/a\ 6 (\ 5a href="cic:/matita/basics/list/length.fix(0,1,1)"\ 6length\ 5/a\ 6 ? (\ 5a href="cic:/matita/tutorial/chapter10/space_enum.def(5)"\ 6space_enum\ 5/a\ 6 Sig (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e1|) (\ 5a title="forget" href="cic:/fakeuri.def(1)"\ 6|\ 5/a\ 6\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 e2|))) in
let sig ≝ (\ 5a href="cic:/matita/tutorial/chapter10/occ.def(7)"\ 6occ\ 5/a\ 6 Sig e1 e2) in
- (\ 5a href="cic:/matita/tutorial/chapter10/bisim.fix(0,2,8)"\ 6bisim\ 5/a\ 6 ? sig n \ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉] \ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]).
+ (\ 5a href="cic:/matita/tutorial/chapter10/bisim.fix(0,2,8)"\ 6bisim\ 5/a\ 6 ? sig n (\ 5a title="Pair construction" href="cic:/fakeuri.def(1)"\ 6〈\ 5/a\ 6e1,e2〉\ 5a title="cons" href="cic:/fakeuri.def(1)"\ 6:\ 5/a\ 6:\ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]) \ 5a title="nil" href="cic:/fakeuri.def(1)"\ 6[\ 5/a\ 6]).
theorem euqiv_sem : ∀Sig.∀e1,e2:\ 5a href="cic:/matita/tutorial/chapter7/re.ind(1,0,1)"\ 6re\ 5/a\ 6 Sig.
\ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 (\ 5a href="cic:/matita/tutorial/chapter10/equiv.def(9)"\ 6equiv\ 5/a\ 6 ? e1 e2) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6 \ 5a title="iff" href="cic:/fakeuri.def(1)"\ 6↔\ 5/a\ 6 \ 5a title="in_l" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e1} \ 5a title="extensional equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 61 \ 5a title="in_l" href="cic:/fakeuri.def(1)"\ 6\sem\ 5/a\ 6{e2}.
definition exp9 ≝ (\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6\ 5a title="re cat" href="cic:/fakeuri.def(1)"\ 6·\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6\ 5a title="re cat" href="cic:/fakeuri.def(1)"\ 6·\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6 \ 5a title="re or" href="cic:/fakeuri.def(1)"\ 6+\ 5/a\ 6 \ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6\ 5a title="re cat" href="cic:/fakeuri.def(1)"\ 6·\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6\ 5a title="re cat" href="cic:/fakeuri.def(1)"\ 6·\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6\ 5a title="re cat" href="cic:/fakeuri.def(1)"\ 6·\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6\ 5a title="re cat" href="cic:/fakeuri.def(1)"\ 6·\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/a.def(9)"\ 6a\ 5/a\ 6)\ 5a title="re star" href="cic:/fakeuri.def(1)"\ 6^\ 5/a\ 6*.
example ex1 : \ 5a title="pair pi1" href="cic:/fakeuri.def(1)"\ 6\fst\ 5/a\ 6 (\ 5a href="cic:/matita/tutorial/chapter10/equiv.def(9)"\ 6equiv\ 5/a\ 6 ? (\ 5a href="cic:/matita/tutorial/chapter10/exp8.def(10)"\ 6exp8\ 5/a\ 6\ 5a title="re or" href="cic:/fakeuri.def(1)"\ 6+\ 5/a\ 6\ 5a href="cic:/matita/tutorial/chapter10/exp9.def(10)"\ 6exp9\ 5/a\ 6) \ 5a href="cic:/matita/tutorial/chapter10/exp9.def(10)"\ 6exp9\ 5/a\ 6) \ 5a title="leibnitz's equality" href="cic:/fakeuri.def(1)"\ 6=\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.con(0,1,0)"\ 6true\ 5/a\ 6.
-normalize // qed.
-
-
+normalize // qed.
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