Theory Sync

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 * Project         : HOL-CSP - A Shallow Embedding of CSP in  Isabelle/HOL
 * Version         : 2.0
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 * Author          : Burkhart Wolff, Safouan Taha, Lina Ye.
 *                   (Based on HOL-CSP 1.0 by Haykal Tej and Burkhart Wolff)
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 * This file       : A Combined CSP Theory
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section‹ The Synchronizing Operator ›

theory  Sync
  imports Process "HOL-Library.Infinite_Set"
begin

subsection‹Basic Concepts›

fun setinterleaving:: "'a trace × ('a event) set × 'a trace  ('a trace)set"
  where

  si_empty1: "setinterleaving([], X, []) = {[]}"
| si_empty2: "setinterleaving([], X, (y # t)) = 
               (if (y  X) 
                then {} 
                else {z. u. z = (y # u)  u  setinterleaving ([], X, t)})"
| si_empty3: "setinterleaving((x # s), X, []) = 
               (if (x  X) 
                then {} 
                else {z. u. z = (x # u)  u  setinterleaving (s, X, [])})"
 
| si_neq   : "setinterleaving((x # s), X, (y # t)) = 
               (if (x  X) 
                then if (y  X) 
                     then if (x = y) 
                          then {z. u. z = (x#u)  u  setinterleaving(s, X, t)} 
                          else {}
                     else {z. u. z = (y#u)  u  setinterleaving ((x#s), X, t)}
                else if (y  X) 
                     then {z. u. z = (x # u)  u  setinterleaving (s, X, (y # t))} 
                           {z. u. z = (y # u)  u  setinterleaving((x # s), X, t)} 
                     else {z. u. z = (x # u)  u  setinterleaving (s, X, (y # t))})"

fun setinterleavingList::"'a trace × ('a event) set × 'a trace  ('a trace)list" 
  where

  si_empty1l: "setinterleavingList([], X, []) = [[]]"
| si_empty2l: "setinterleavingList([], X, (y # t)) = 
               (if (y  X) 
                then [] 
                else map (λz. y#z) (setinterleavingList ([], X, t)))"
| si_empty3l: "setinterleavingList((x # s), X, []) = 
               (if (x  X) 
                then [] 
                else map (λz. x#z) (setinterleavingList (s, X, [])))"

 
 
| si_neql   : "setinterleavingList((x # s), X, (y # t)) = 
               (if (x  X) 
                then if (y  X) 
                     then if (x = y) 
                          then map (λz. x#z)  (setinterleavingList(s, X, t))
                          else []
                     else map (λz. y#z)  (setinterleavingList ((x#s), X, t))
                else if (y  X) 
                     then map (λz. x#z)  (setinterleavingList (s, X, (y # t)))
                          @ map (λz. y#z)  (setinterleavingList ((x#s), X, t)) 
                     else map (λz. x#z)  (setinterleavingList (s, X, (y # t))))"

lemma finiteSetinterleavingList: "finite (set (setinterleavingList(s, X, t)))" 
  by auto

lemma sym : "setinterleaving(s, X, t)= setinterleaving(t, X, s)"
  by (rule setinterleaving.induct[of "λ(s,X,t). setinterleaving (s, X, t) 
  = setinterleaving (t, X, s)" "(s, X, t)", simplified], auto)

 

abbreviation "setinterleaves_syntax"  ("_ setinterleaves '(()'(_, _')(), _')" [60,0,0,0]70)
  where      "u setinterleaves ((s, t), X) == (u  setinterleaving(s, X, t))"

 
subsection‹Definition›

definition Sync :: "['a process,'a set,'a process] => 'a process"    ("(3(_ _/ _))" [64,0,65] 64)  
  where "P  A  Q   Abs_process({(s,R). t u X Y. (t,X)   P  (u,Y)   Q  
                                                    (s setinterleaves ((t,u),(ev`A)  {tick}))  
                                                    R = (X  Y)  ((ev`A)  {tick})  X  Y}     
                                  {(s,R). t u r v. front_tickFree v  (tickFree r  v=[])  
                                                    s = r@v  
                                                    (r setinterleaves ((t,u),(ev`A)  {tick}))  
                                                    (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)},
                   
                                  {s.    t u r v. front_tickFree v  (tickFree r  v=[])  
                                                   s = r@v  
                                                   (r setinterleaves ((t,u),(ev`A)  {tick}))  
                                                   (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)})"

subsection‹Consequences›

lemma emptyLeftProperty:"s. s setinterleaves (([], t), A)s=t" 
  apply(induct_tac t)  
   apply simp 
  by auto 

lemma emptyLeftSelf: " (t1. t1 set tt1A)t setinterleaves (([], t), A) "
  apply(induct_tac t)
   apply simp 
  by auto

lemma emptyLeftNonSync: "s. s setinterleaves (([], t), A)(t1. t1 set tt1A)"
  apply(induct_tac t)
   apply simp
proof-
  fix a list
  assume a: "s. s setinterleaves (([], list), A)  (t1. t1  set list  t1  A)"
  thus "s. s setinterleaves (([], a # list), A)  (t1. t1  set (a # list)  t1  A)"
  proof-
    have th: "s setinterleaves (([], a # list), A)aA" by auto
    obtain s1 where th1: "s setinterleaves (([], a # list), A)s1 setinterleaves (([], list), A)"  
      using mem_Collect_eq th by fastforce
    from a th1 have th2: "s. s setinterleaves (([], a # list), A)(t. t set listt  A)" 
      by auto
    with a show ?thesis   
      by (metis (no_types, lifting) empty_iff set_ConsD setinterleaving.simps(2))   
  qed
qed
 

lemma ftf_Sync1: "a  set(u)  a  set(t)  s setinterleaves ((t, u), A)  a  set(s)"
proof (induction "length t + length u" arbitrary:s t u rule:nat_less_induct)
  case 1
  show ?case 
    apply(cases t) using sym emptyLeftProperty apply blast
    apply(cases u) using sym emptyLeftProperty apply blast
    apply(simp split:if_splits, intro conjI impI, elim conjE disjE exE)
         apply (metis "1.hyps" add_less_le_mono length_Cons lessI order_refl set_ConsD)
        apply (metis "1.hyps" add_Suc_right length_Cons lessI set_ConsD) 
       apply (metis "1.hyps" add_less_mono length_Cons lessI set_ConsD) 
      apply (metis "1.hyps" add_Suc_right length_Cons lessI set_ConsD) 
     apply (metis (no_types, opaque_lifting) "1.hyps" add.commute add_Suc_right insert_iff 
                                         length_Cons lessI list.simps(15)) 
    by (metis "1.hyps" add_less_le_mono length_Cons lessI order_refl set_ConsD)
qed

lemma addNonSyncEmpty: "sa setinterleaves (([], u), A)  y1  A 
    (sa @ [y1]) setinterleaves (([y1], u), A)  (sa @ [y1]) setinterleaves (([], u @ [y1]), A)"
  proof (induction "length u" arbitrary:sa u rule:nat_less_induct)
    case 1
    then show ?case 
      apply(cases u) 
       apply simp 
    proof-
      fix a list
      assume a: "m<length u. x. m = length x (xa. xa setinterleaves (([], x), A)  y1  A 
       (xa @ [y1]) setinterleaves (([y1], x), A)  (xa @ [y1]) setinterleaves (([], x @ [y1]), A))"
      and b: "u = a # list"
      from b have th: "sa setinterleaves (([], u), A)(tl sa) setinterleaves (([], list), A)"  
        by (metis emptyLeftNonSync emptyLeftProperty emptyLeftSelf list.distinct(1) list.sel(3) 
        list.set_sel(2))
      from a b th have th1: "sa setinterleaves (([], u), A)  y1  A ((tl sa) @ [y1]) 
      setinterleaves (([y1], list), A)((tl sa)@[y1]) setinterleaves (([], list@[y1]), A)" by auto
      thus "sa setinterleaves (([], u), A)  y1  A 
        (sa @ [y1]) setinterleaves (([y1], u), A)  (sa @ [y1]) setinterleaves (([], u @ [y1]), A)"
        using  b th by auto  
    qed
  qed

lemma addNonSync: "sa setinterleaves ((t,u),A) y1  A
(sa@[y1]) setinterleaves ((t@[y1],u),A)(sa@[y1]) setinterleaves ((t,u@[y1]),A)"
proof (induction "length t + length u" arbitrary:sa t u rule:nat_less_induct)
  case 1
  then show ?case  
    apply(cases t)   
     apply (simp add: addNonSyncEmpty) 
    apply (cases u) 
     apply (metis Sync.sym addNonSyncEmpty append_self_conv2) 
  proof-
    fix a list aa lista
    assume a: "m<length t + length u. x xa. m = length x + length xa 
    (xb. xb setinterleaves ((x, xa), A)  y1  A (xb @ [y1]) setinterleaves ((x @ [y1], xa), A) 
     (xb @ [y1]) setinterleaves ((x, xa @ [y1]), A))"
    and b: " t = a # list" 
    and c: "u = aa # lista"
    thus " sa setinterleaves ((t, u), A)  y1  A 
     (sa @ [y1]) setinterleaves ((t @ [y1], u), A)  (sa @ [y1]) setinterleaves ((t, u @ [y1]), A)"
     proof-
       from b c have th0pre: "a=aaaa Asa setinterleaves ((t, u), A) 
                              (tl sa) setinterleaves ((list,lista), A)" by auto
       from th0pre a b c have th0pre1: "a=aaaa Asa setinterleaves ((t, u), A) y1  A
       ((tl sa) @ [y1]) setinterleaves ((list@ [y1], lista), A)
       ((tl sa) @ [y1]) setinterleaves ((list, lista@ [y1]), A)"  
        by (metis add_less_mono length_Cons lessI)  
      from  th0pre th0pre1 b c have th0: "a=aaaa Asa setinterleaves ((t, u), A)  y1  A 
      (sa @ [y1]) setinterleaves ((t @ [y1], u), A)(sa @ [y1]) setinterleaves ((t, u @ [y1]), A)"  
        by auto 
      from b c have th1pre: "aAaa Asa setinterleaves ((t, u), A) 
                             (tl sa) setinterleaves ((list,aa#lista), A)" by auto
      from th1pre a b c have th1pre1: "aAaa Asa setinterleaves ((t, u), A) y1  A
      ((tl sa) @ [y1]) setinterleaves ((list@ [y1], aa#lista), A)
      ((tl sa) @ [y1]) setinterleaves ((list, aa#lista@ [y1]), A)"  
        by (metis add_Suc append_Cons length_Cons lessI) 
      from  th1pre th1pre1 b c  have th1: "aAaa Asa setinterleaves ((t, u), A)  y1  A   
      (sa @ [y1]) setinterleaves ((t @ [y1], u), A)(sa @ [y1]) setinterleaves ((t, u @ [y1]), A)" 
        by auto  
      from b c have th2pre: "aaAa Asa setinterleaves ((t, u), A) 
                             (tl sa) setinterleaves ((a#list,lista), A)" by auto
      from th2pre a b c have th2pre1: "aaAa Asa setinterleaves ((t, u), A) y1  A
      ((tl sa) @ [y1]) setinterleaves ((a#list@ [y1], lista), A)
      ((tl sa) @ [y1]) setinterleaves ((a#list, lista@ [y1]), A)"  
        by (metis add_Suc_right append_Cons length_Cons lessI)  
      from  th2pre th2pre1 b c have th2: "aaAa Asa setinterleaves ((t, u), A)  y1  A  
      (sa @ [y1]) setinterleaves ((t @ [y1], u), A)(sa @ [y1]) setinterleaves ((t, u @ [y1]), A)" 
        by auto
      from b c have th3pre: "aaAa Asa setinterleaves ((t, u), A)
     (tl sa) setinterleaves ((a#list,lista), A)(tl sa)setinterleaves ((list,aa#lista), A)" by auto
      from th3pre a b c have th3pre1: "aaAa Asa setinterleaves ((t, u), A)
      (tl sa) setinterleaves ((a#list,lista), A) y1  A 
      ((tl sa) @ [y1]) setinterleaves ((a#list@ [y1], lista ), A)((tl sa) @ [y1]) setinterleaves 
      ((a#list, lista@ [y1] ), A)" 
        by (metis add_Suc_right append_Cons length_Cons lessI)  
      from th3pre a b c have th3pre2: "aaAa Asa setinterleaves ((t, u), A)
      (tl sa) setinterleaves ((list,aa#lista), A) y1  A ((tl sa) @ [y1]) setinterleaves 
      ((list@ [y1], aa#lista ), A)((tl sa) @ [y1]) setinterleaves ((list, aa#lista @ [y1]), A)"  
        by (metis add_Suc append_Cons length_Cons lessI)         
      from th3pre th3pre1 th3pre2 a b c have th3: "aaAa Asa setinterleaves ((t, u), A)  
      y1  A (sa @ [y1]) setinterleaves ((t @ [y1], u), A)  
      (sa @ [y1]) setinterleaves ((t, u @ [y1]), A)" by auto 
      show ?thesis  
        using b c th0 th1 th2 th3 by auto
    qed
  qed
qed

lemma addSyncEmpty: "sa setinterleaves (([], u), A)  y1  A  
                    (sa @ [y1]) setinterleaves (([y1], u @ [y1]), A)"
  proof (induction "length u" arbitrary:sa u rule:nat_less_induct)
    case 1
    then show ?case 
      apply(cases u) 
       apply simp 
    proof-
      fix a list
      assume a: "m<length u. x. m = length x (xa. xa setinterleaves (([], x), A)  y1  A 
                  (xa @ [y1]) setinterleaves (([y1], x @ [y1]), A))"
      and b: "u = a # list"  
      from b have th: "sa setinterleaves (([], u), A)(tl sa) setinterleaves (([], list), A)"  
        by (metis emptyLeftNonSync emptyLeftProperty emptyLeftSelf list.distinct(1) list.sel(3) 
           list.set_sel(2))
      from a th have th1: "sa setinterleaves (([], u), A)  y1  A 
      ((tl sa) @ [y1]) setinterleaves (([y1], list @ [y1]), A)" using b by auto
      thus "sa setinterleaves (([], u), A)  y1  A  
           (sa @ [y1]) setinterleaves (([y1], u @ [y1]), A)" using b th by auto  
    qed
  qed 
 
lemma addSync: "sa setinterleaves ((t,u),A) y1  A(sa@[y1]) setinterleaves ((t@[y1],u@[y1]),A)"
proof (induction "length t + length u" arbitrary:sa t u rule:nat_less_induct)
  case 1
  then show ?case 
    apply(cases t) 
     apply (simp add: addSyncEmpty)
    apply(cases u) 
     apply (metis Sync.sym addSyncEmpty append.left_neutral) 
  proof-
    fix a list aa lista
    assume a: "m<length t + length u. x xa. m = length x + length xa 
                 (xb. xb setinterleaves ((x, xa), A)  y1  A  (xb @ [y1]) setinterleaves 
                 ((x @ [y1], xa @ [y1]), A))"
    and b: "t = a # list "
    and c: " u = aa # lista"
    thus "sa setinterleaves((t, u),A)y1 A(sa @ [y1]) setinterleaves ((t @ [y1], u @ [y1]), A)"
    proof-
      from b c have th0pre: "a=aaaa Asa setinterleaves ((t, u), A) 
      (tl sa) setinterleaves ((list,lista), A)" by auto
      from th0pre a b c have th0pre1: "a=aaaa Asa setinterleaves ((t, u), A) y1  A
      ((tl sa) @ [y1]) setinterleaves ((list@ [y1], lista @ [y1]), A)"  
        by (metis add_less_mono length_Cons lessI)  
      from  th0pre th0pre1 b c have th0: "a=aaaAsa setinterleaves ((t, u), A)  y1  A  
      (sa @ [y1]) setinterleaves ((t @ [y1], u @ [y1]), A)" by auto 
      from b c have th1pre: "aAaa Asa setinterleaves ((t, u), A) 
      (tl sa) setinterleaves ((list,aa#lista), A)" by auto
      from th1pre a b c have th1pre1: "aAaa Asa setinterleaves ((t, u), A) y1  A
      ((tl sa) @ [y1]) setinterleaves ((list@ [y1], aa#lista @ [y1]), A)"  
        by (metis add_Suc append_Cons length_Cons lessI) 
      from  th1pre th1pre1 b c  have th1: "aAaa Asa setinterleaves ((t, u), A)  y1  A  
      (sa @ [y1]) setinterleaves ((t @ [y1], u @ [y1]), A)" by auto  
      from b c have th2pre: "aaAa Asa setinterleaves ((t, u), A) 
      (tl sa) setinterleaves ((a#list,lista), A)" by auto
      from th2pre a b c have th2pre1: "aaAa Asa setinterleaves ((t, u), A) y1  A
      ((tl sa) @ [y1]) setinterleaves ((a#list@ [y1], lista @ [y1]), A)"  
        by (metis add_Suc_right append_Cons length_Cons lessI)  
      from  th2pre th2pre1 b c have th2: "aaAa Asa setinterleaves ((t, u), A)  y1  A  
      (sa @ [y1]) setinterleaves ((t @ [y1], u @ [y1]), A)" by auto
      from b c have th3pre: "aaAa Asa setinterleaves ((t, u), A)
      (tl sa) setinterleaves((a#list,lista), A)(tl sa)setinterleaves ((list,aa#lista), A)" by auto
      from th3pre a b c have th3pre1: "aaAa Asa setinterleaves ((t, u), A)
      (tl sa) setinterleaves ((a#list,lista), A) y1  A 
      ((tl sa) @ [y1]) setinterleaves ((a#list@ [y1], lista @ [y1]), A)" 
        by (metis add_Suc_right append_Cons length_Cons lessI)  
      from th3pre a b c have th3pre2: "aaAa Asa setinterleaves ((t, u), A)
      (tl sa) setinterleaves ((list,aa#lista), A) y1  A 
      ((tl sa) @ [y1]) setinterleaves ((list@ [y1], aa#lista @ [y1]), A)" 
        by (metis add_Suc append_Cons length_Cons lessI)         
      from th3pre th3pre1 th3pre2 a b c have th3: "aaAa Asa setinterleaves ((t, u), A)  
      y1  A  (sa @ [y1]) setinterleaves ((t @ [y1], u @ [y1]), A)" by auto 
      show ?thesis  
        using b c th0 th1 th2 th3 by auto
    qed
  qed
qed
 

lemma doubleReverse: "s1 setinterleaves ((t, u), A)(rev s1) setinterleaves ((rev t, rev u), A)"
proof (induction "length t + length u" arbitrary:s1 t u rule:nat_less_induct)
  case 1
  then show ?case 
    apply(cases t)  
    using emptyLeftNonSync 
     apply (metis emptyLeftProperty emptyLeftSelf rev.simps(1) set_rev)  
    apply(cases u) 
    using sym 
     apply (metis (no_types, lifting) emptyLeftNonSync emptyLeftProperty emptyLeftSelf 
     rev.simps(1) set_rev) 
  proof-
    fix a list aa lista
    assume a: "m<length t + length u. x xa. m = length x + length xa 
               (xb. xb setinterleaves ((x, xa), A) rev xb setinterleaves ((rev x, rev xa), A))"
    and b: "t = a # list"
    and c: "u = aa # lista"
    thus "s1 setinterleaves ((t, u), A) rev s1 setinterleaves ((rev t, rev u), A)"  
    proof-
      from b c have th0pre: "a=aaaa As1 setinterleaves ((t, u), A)
      (tl s1) setinterleaves ((list,lista), A)" by auto
      from th0pre a b c have th0pre1: "a=aaaa As1 setinterleaves ((t, u), A)
      ((rev (tl s1)) setinterleaves ((rev list, rev lista), A))"  
        by (metis add_less_mono length_Cons lessI)
      from  th0pre th0pre1 b c have th0: "a=aaaa As1 setinterleaves ((t, u), A) 
      rev s1 setinterleaves ((rev t, rev u), A)"   using addSync by fastforce 
      from b c have th1pre: "aAaa As1 setinterleaves ((t, u), A)
      (tl s1) setinterleaves ((list,aa#lista), A)" by auto
      from th1pre a b c have th1pre1: "aAaa As1 setinterleaves ((t, u), A)
      ((rev (tl s1)) setinterleaves ((rev list, rev (aa#lista)), A))"  
        by (metis add_less_mono1 length_Cons lessI)          
      from  th1pre th1pre1 b c have th1: "aAaa As1 setinterleaves ((t, u), A) 
      rev s1 setinterleaves ((rev t, rev u), A)"  using addNonSync by fastforce  
      from b c have th2pre: "aaAa As1 setinterleaves ((t, u), A)
      (tl s1) setinterleaves ((a#list,lista), A)" by auto
      from th2pre a b c have th2pre1: "aaAa As1 setinterleaves ((t, u), A)
      ((rev (tl s1)) setinterleaves ((rev (a#list), rev lista), A))"  
        by (metis add_Suc_right length_Cons lessI)        
      from  th2pre th2pre1 b c have th2: "aaAa As1 setinterleaves ((t, u), A) 
      rev s1 setinterleaves ((rev t, rev u), A)"  
        using addNonSync by fastforce 
      from b c have th3pre: "aaAa As1 setinterleaves ((t, u), A)
      (tl s1) setinterleaves ((a#list,lista),A)(tl s1) setinterleaves((list,aa#lista), A)" by auto
      from th3pre a b c have th3pre1: "aaAa As1 setinterleaves ((t, u), A)
      (tl s1) setinterleaves ((a#list,lista), A) 
      ((rev (tl s1)) setinterleaves ((rev (a#list), rev (lista)), A))"   
        by (metis add_Suc_right length_Cons lessI)
      from th3pre a b c have th3pre2: "aaAa As1 setinterleaves ((t, u), A)
      (tl s1) setinterleaves ((list,aa#lista), A) 
      ((rev (tl s1)) setinterleaves ((rev (list), rev (aa#lista)), A))"  
        by (metis add_less_mono1 length_Cons lessI)
      from  th3pre1 have th3pre31: "aaAa As1 setinterleaves ((t, u), A)
      ((rev (tl s1)) setinterleaves ((rev (a#list), rev (lista)), A))
      ((rev (tl s1))@[aa]) setinterleaves ((rev (a#list), (rev (lista))@[aa]), A)"
        by (simp add: addNonSync)
      from  th3pre2 have th3pre32: "aaAa As1 setinterleaves ((t, u), A)
      ((rev (tl s1)) setinterleaves ((rev (list), rev (aa#lista)), A))
      ((rev (tl s1))@[a]) setinterleaves (((rev (list)@[a]), (rev (aa#lista))), A)"
        by (simp add: addNonSync)
      from th3pre th3pre1 th3pre2 th3pre31 th3pre32 a b c have th3: "aaAa A
      s1 setinterleaves ((t, u), A) rev s1 setinterleaves ((rev t, rev u), A)" by force
      show?thesis  
        using b c th0 th1 th2 th3 by auto
    qed 
  qed
qed
 
 
lemma  ftf_Sync21: "(aset(u)aset(t)aset(t)aset(u))aAsetinterleaving(u, A ,t)= {}"
proof (induction "length t + length u" arbitrary: t u rule:nat_less_induct)
  case 1
  then show ?case 
    apply(cases t)  
    using Sync.sym emptyLeftNonSync apply fastforce 
    apply(cases u)  
     apply auto[1]
    apply(simp split:if_splits, intro conjI impI, elim conjE disjE exE)
             apply blast
            apply auto[1]  
           apply blast 
          apply auto[1]  
         apply auto[1]  
    using less_SucI apply blast  
       apply auto[1] 
      apply auto[1]  
    using list.simps(15) apply auto[1] 
    by auto 
qed

lemma ftf_Sync32: "u=u1@[tick]t=t1@[tick]s setinterleaves ((t, u), insert tick (ev ` A))
                  s1. s1 setinterleaves ((t1, u1), insert tick (ev ` A)) (s=s1@[tick])"
proof-
  assume h: "u=u1@[tick]t=t1@[tick]s setinterleaves ((t, u), insert tick (ev ` A))"
  thus "s1. s1 setinterleaves ((t1, u1), insert tick (ev ` A)) (s=s1@[tick])"
  proof-
    from h have a:"rev u=tick#rev u1" by auto
    from h have b:"rev t=tick#rev t1" by auto
    from h have ab: "(rev s)  setinterleaves ((tick#rev t1, tick#rev u1), insert tick (ev ` A))" 
      using doubleReverse by fastforce
    from h obtain ss where c: "ss  setinterleaves  ((rev t1, rev u1), insert tick (ev ` A)) 
    ss=tl(rev s)" using ab by auto 
    from c have d: "(rev ss)  setinterleaves  (( t1,  u1), insert tick (ev ` A))" 
      using doubleReverse by fastforce
    from d have e: "rev s=tick#ss"  
      using ab append_Cons_eq_iff c by auto
    show ?thesis  
      using d e by blast
  qed
qed


lemma SyncWithTick_imp_NTF: 
  "(s @ [tick]) setinterleaves ((t, u),insert tick (ev ` A)) 
    t 𝒯 P  u  𝒯 Q
    t1 u1. t=t1@[tick]  u=u1@[tick] s setinterleaves ((t1, u1), insert tick (ev ` A))"  
proof-
  assume h: "(s @ [tick]) setinterleaves ((t, u), insert tick (ev ` A))"
  and h1: "t 𝒯 P"
  and h2: "u 𝒯 Q"
  thus "t1 u1. t=t1@[tick]  u=u1@[tick] s setinterleaves ((t1, u1), insert tick (ev ` A))"
  proof-
    from h have a: "(tick#rev s) setinterleaves ((rev t, rev u), insert tick (ev ` A))" 
      using doubleReverse by fastforce
    from h obtain tt uu where b: "t=tt@[tick]u=uu@[tick]"  
      by (metis T_nonTickFree_imp_decomp empty_iff ftf_Sync1 ftf_Sync21 h1 h2 insertI1 
          non_tickFree_tick tickFree_append tickFree_def)
    from h b have d: "s setinterleaves ((tt, uu), insert tick (ev ` A))"  
      using ftf_Sync32 by blast
    show ?thesis  
      using b d by blast
  qed 
qed

lemma synPrefix1: 
   " ta = [] 
      t1 u1. (s @ t) setinterleaves ((ta, u), A)   
                 t1  ta  u1  u  s setinterleaves ((t1, u1), A)"
proof-
  assume a: "ta = []"
  obtain u1 where th: "u1=s" by blast
  from a have th2: "(s @ t) setinterleaves ((ta, u), A)  (s @ t)= u"  
    by (simp add: a emptyLeftProperty)
  from a have th3: "(s @ t) setinterleaves ((ta, u), A)  (t1. t1set ut1A)"  
    by (simp add: emptyLeftNonSync)
  from a th have th1: "(s @ t) setinterleaves ((ta, u), A)  []  ta  u1  u " 
    using le_list_def th2 by blast 
  from a th have thh1: "(s @ t) setinterleaves ((ta, u), A) (t1. t1set u1t1A)  
  s setinterleaves (([], u1), A)"  by (simp add: emptyLeftSelf)
  thus "t1 u1. (s @ t) setinterleaves ((ta, u), A)  t1  ta  u1  u  
  s setinterleaves ((t1, u1), A)" using th th1 th2 th3 thh1 by fastforce 
qed
 

lemma synPrefix: "t1 u1. (s @ t) setinterleaves ((ta, u), A)
                  t1tau1us setinterleaves ((t1, u1), A)"
proof (induction "length ta + length u" arbitrary: s t ta u rule:nat_less_induct)
  case 1
  then show ?case 
    apply(cases ta)  
     using synPrefix1 apply fastforce 
    apply(cases u) 
     using sym synPrefix1 apply metis 
   proof-
     fix a list aa lista s t
     assume a: " m<length ta + length u. x xa. m = length x + length xa 
                 (xb xc. t1 u1. (xb @ xc) setinterleaves ((x, xa), A) 
                 t1  x  u1  xa  xb setinterleaves ((t1, u1), A))"
     and b: "ta = a # list"
     and c: "u = aa # lista " 
     thus " t1 u1. (s @ t) setinterleaves ((ta, u), A)  t1  ta  u1  u  
            s setinterleaves ((t1, u1), A)" 
     proof-
       from a have th0: "xb xc. t1 u1. (xb @ xc) setinterleaves ((list, lista), A) 
                                  t1  list  u1  lista  xb setinterleaves ((t1, u1), A)"  
         by (metis add_less_le_mono b c impossible_Cons le_cases not_le_imp_less)
       from b c obtain yb where thp: "a=aaa A(s@t) setinterleaves ((ta, u), A)length s >1 
       yb=tl s" by blast
       with b c have thp4: "a=aaa A(s @ t) setinterleaves ((ta, u), A)length s >1 s=a#yb" 
         by (auto, metis Cons_eq_append_conv list.sel(3) list.size(3) not_less0)
       have thp5: "a=aaa A(s @ t) setinterleaves ((ta, u), A)length s >1 
       (yb @ t) setinterleaves ((list, lista), A)"  using b c thp4 by auto 
       from th0 obtain yt yu where thp1: "a = aa  a  A  (s @ t) setinterleaves ((ta, u), A)  
       1 < length syb setinterleaves ((yt, yu), A)ytlistyulista"  using thp5 by blast 
       from thp thp1 have thp2: "a=aaa A (s @ t) setinterleaves ((ta, u), A) length s >1 
       s setinterleaves ((a#yt, aa#yu), A)" using thp4 by auto 
       from b c have thp3: "a=aaa A (s @ t) setinterleaves ((ta, u), A)  length s=1
       s setinterleaves (([a], [aa]), A)" 
         using append_eq_append_conv2[of s t "[aa]"] by (auto, metis append_Nil2 
         append_eq_append_conv length_Cons list.size(3))
       have thp6: "a=aaa A (s @ t) setinterleaves ((ta, u), A)  length s=0
       s setinterleaves (([], []), A)" by auto
       from thp1 have thp7: "a=aaa A (s @ t) setinterleaves ((ta, u), A) length s >1
       (a # yt)ta (aa # yu)u"  by (metis b c le_less less_cons)  
       have th: "a=aaa At1 u1. (s @ t) setinterleaves ((ta, u), A)  
       t1  ta  u1  u  s setinterleaves ((t1, u1), A)"
       proof -
         assume dd:"a=aa  a A"
         consider (aa) "length s = 0" | (bb) "length s = 1" | (cc) "length s > 1"
           by linarith
         then show ?thesis 
         proof cases 
           case aa
           with thp6 show ?thesis 
             by (rule_tac x="[]" in exI, rule_tac x="[]" in exI, simp) 
         next
           case bb
           with dd thp3 b c show ?thesis 
             by (rule_tac x="[a]" in exI, rule_tac x="[a]" in exI, auto simp add: le_list_def)            
         next
           case cc
           with dd thp2 thp7 b c show ?thesis
             by (rule_tac x="a#yt" in exI, rule_tac x="a#yu" in exI, auto simp add: le_list_def)   
        qed
      qed
      from b c have th1pre: "aAaa A(s @ t) setinterleaves ((ta, u), A) 
      tl (s @ t) setinterleaves ((list, u), A)hd (s@t)=a" by auto 
      from a b c obtain yt1 yu1 where th1pre1: "aAaa A(s @ t) setinterleaves ((ta, u), A)
      length s>0yt1list yu1  u tl s setinterleaves ((yt1, yu1), A)"  
        by (metis (no_types, lifting) length_Cons length_greater_0_conv lessI plus_nat.simps(2) 
        th1pre tl_append2)
      from b have th1pre2: "yt1lista#yt1ta"  
        by (simp add: le_less less_cons) 
      from b c have th1pre3: "aAaa Atl s setinterleaves ((yt1, yu1), A)
      (a#(tl s)) setinterleaves ((a#yt1, yu1), A)"  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident)  
      from b c th1pre1 th1pre2 have th1pre4: "aAaa A(s @ t) setinterleaves ((ta, u), A)
      length s>0 a#yt1ta yu1 u s setinterleaves ((a#yt1, yu1), A)" 
        using th1pre th1pre3  by fastforce  
      have th1pre5:"aAaa A(s @ t) setinterleaves ((ta, u), A)length s=0 []ta [] u 
      s setinterleaves (([], []), A)" by auto
      have th1: "aAaa At1 u1. (s @ t) setinterleaves ((ta, u), A)  
      t1  ta  u1  u  s setinterleaves ((t1, u1), A)"  using th1pre4 th1pre5 by blast 
      from b c have th2pre: "aaAa A(s @ t) setinterleaves ((ta, u), A) 
      tl (s @ t) setinterleaves ((ta, lista), A)hd (s@t)=aa" by auto 
      from a b c obtain yt2 yu2 where th2pre1: "aaAa A(s @ t) setinterleaves ((ta, u), A)
      length s>0yt2ta yu2  lista (tl s) setinterleaves ((yt2, yu2), A)"  
        by (metis (no_types, lifting) add_Suc_right length_Cons length_greater_0_conv lessI 
        th2pre tl_append2)  
      from c have th2pre2: "yu2listaaa#yu2u"   
        by (simp add: le_less less_cons) 
      from b c have th2pre3: "aaAa Atl s setinterleaves ((yt2, yu2), A)
      (aa#(tl s)) setinterleaves ((yt2, aa#yu2), A)"  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident)  
      from b c th2pre1 th2pre2 have th2pre4: "aaAa A(s @ t) setinterleaves ((ta, u), A)
      length s>0 yt2ta aa#yu2 u s setinterleaves ((yt2, aa#yu2), A)" 
        using th2pre th2pre3  by fastforce  
      have th2pre5:"aaAa A(s @ t) setinterleaves ((ta, u), A)length s=0 
      []ta [] u s setinterleaves (([], []), A)" by auto
      have th2: "aaAa At1 u1. (s @ t) setinterleaves ((ta, u), A)  
      t1  ta  u1  u  s setinterleaves ((t1, u1), A)"  using th2pre4 th2pre5 by blast      
      from b c have th3pre: "aaAa A(s @ t) setinterleaves ((ta, u), A)tl (s @ t) 
      setinterleaves ((ta, lista), A)hd (s@t)=aatl (s @ t)setinterleaves((list, u), A)hd(s@t)=a" 
        by auto
      from a b c th3pre obtain yt31 yu31 where th3pre1: "aaAa A
      (s @ t) setinterleaves ((ta, u), A)tl (s @ t) setinterleaves ((ta, lista), A)
      hd (s@t)=aalength s>0yt31ta yu31  lista (tl s) setinterleaves ((yt31, yu31), A)" 
        by(metis(no_types,lifting)add_Suc_right length_Cons length_greater_0_conv lessI tl_append2) 
      from a b c th3pre obtain yt32 yu32 where th3pre2: "aaAaA(s@t)setinterleaves ((ta, u),A)
      tl (s @ t) setinterleaves ((list, u), A)hd (s@t)=alength s>0yt32list yu32 u 
      (tl s) setinterleaves ((yt32, yu32), A)"  
        by (metis add_less_mono1 impossible_Cons le_neq_implies_less length_greater_0_conv 
        nat_le_linear tl_append2)
      from b c have th3pre3: "aaAa Atl s setinterleaves ((yt31, yu31), A)
      (aa#(tl s)) setinterleaves ((yt31, aa#yu31), A)"  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident) 
      from b c th3pre1 th3pre2 have th3pre4: "aaAa A(s @ t) setinterleaves ((ta, u), A)
      length s>0tl (s @ t) setinterleaves ((ta, lista), A)hd (s@t)=aa yt31ta aa#yu31 u 
      s setinterleaves ((yt31, aa#yu31), A)"  
        by (metis hd_append2 le_less length_greater_0_conv less_cons list.exhaust_sel th3pre3)
      from b c have th3pre5: "aaAa Atl s setinterleaves ((yt32, yu32), A)
      (a#(tl s)) setinterleaves ((a#yt32, yu32), A)"  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident) 
      from b c th3pre1 th3pre2 have th3pre6: "aaAa A(s @ t) setinterleaves ((ta, u), A)
      length s>0tl (s @ t) setinterleaves ((list, u), A)hd (s@t)=a a#yt32ta yu32 u 
      s setinterleaves ((a#yt32, yu32), A)" 
        using th3pre th3pre5  by (metis hd_append2 le_less length_greater_0_conv less_cons 
        list.exhaust_sel)
      have th3pre7:"aaAa A(s @ t) setinterleaves ((ta, u), A)length s=0 
      []ta [] u s setinterleaves (([], []), A)" by auto
      have th3: "aaAa At1 u1. (s @ t) setinterleaves ((ta, u), A)  
      t1  ta  u1  u  s setinterleaves ((t1, u1), A)"  
        using th3pre th3pre4 th3pre6 th3pre7 by blast 
      with a b c th th1 th2 show ?thesis
        by fastforce
    qed
  qed
qed

lemma SyncWithTick_imp_NTF1: 
"(s @ [tick]) setinterleaves ((t, u), insert tick (ev ` A)) 
  t 𝒯 P  u 𝒯 Q
   t u Xa Y. (t, Xa)   P  ( (u, Y)   Q  
                 s setinterleaves ((t, u), insert tick (ev ` A))  
                 X - {tick} = (Xa  Y)  insert tick (ev ` A)  Xa  Y)"
  apply (drule SyncWithTick_imp_NTF)
    apply simp
   apply simp 
proof -
  assume A: "t  𝒯 P"
  and B: "u  𝒯 Q"
  and C: "t1 u1. t = t1 @ [tick]u = u1@[tick]s setinterleaves ((t1, u1), insert tick (ev ` A))" 
  from C obtain t1 u1 
    where D: "t = t1 @ [tick]  u = u1 @ [tick]  
                  s setinterleaves ((t1, u1), insert tick (ev ` A))" by blast
  from A B D have E: "(t1, X-{tick})   P  (u1, X-{tick})   Q"  
    by (simp add: T_F process_charn)  
  thus  " t u Xa Y. (t, Xa)   P  (u, Y)   Q  
                     s setinterleaves ((t, u), insert tick (ev ` A))  
                     X - {tick} = (Xa  Y)  insert tick (ev ` A)  Xa  Y"
    using A B C D E by blast
qed

lemma ftf_Sync: 
  "front_tickFree u
    front_tickFree t
    s setinterleaves ((t, u),insert tick (ev ` A))
    front_tickFree s"
proof-
  assume A: "front_tickFree u"
  assume B: "front_tickFree t"
  assume C: "s setinterleaves ((t, u), insert tick (ev ` A))"
  thus "front_tickFree s" 
  proof-
    from A obtain u1 where A1: " u2. u1utickFree u1  (u2utickFree u2u2u1)"   
      by (metis append.right_neutral append_eq_first_pref_spec front_tickFree_charn le_list_def 
         tickFree_Nil)
    from A A1 have AA1: "u1=uu=u1@[tick]" 
      by (metis(no_types, lifting) antisym append_Nil2 append_eq_first_pref_spec append_is_Nil_conv 
      front_tickFree_charn le_list_def less_list_def less_self nonTickFree_n_frontTickFree)
    from B obtain t1 where B1: " t2. t1ttickFree t1  (t2ttickFree t2t2t1)"
      by (metis append.right_neutral append_eq_first_pref_spec front_tickFree_charn le_list_def 
      tickFree_Nil)
    from B B1 have BB1: "t1=tt=t1@[tick]" 
      by (metis(no_types, lifting) antisym append_Nil2 append_eq_first_pref_spec append_is_Nil_conv 
      front_tickFree_charn le_list_def less_list_def less_self nonTickFree_n_frontTickFree)
    from A1 B1 have C1: "s1. s1 setinterleaves ((t1, u1), insert tick (ev ` A))tickFree s1"  
      by (meson ftf_Sync1 tickFree_def)
    from AA1 BB1 have CC1: "u1=ut1=ttickFree s" 
      by (simp add: C C1)
    from AA1 BB1 have CC2: "u1=ut=t1@[tick]tickFree s"  using ftf_Sync21  
      by (metis A1 C equals0D insertI1 non_tickFree_tick tickFree_append tickFree_def)
    from AA1 BB1 have CC3: "u=u1@[tick]t1=ttickFree s"  using ftf_Sync21 
      by (metis B1 C insertI1 insert_not_empty mk_disjoint_insert non_tickFree_tick tickFree_append 
      tickFree_def) 
    from AA1 BB1 have CC4: "u=u1@[tick]t=t1@[tick]
    s1. s1 setinterleaves ((t1, u1), insert tick (ev ` A))(s=s1@[tick])"  
      using C ftf_Sync32 by blast  
    from C1 CC4 have CC5: "front_tickFree s"  
      using AA1 BB1 CC1 CC2 CC3 tickFree_implies_front_tickFree 
      tickFree_implies_front_tickFree_single by auto
    with A1 B1 C1 AA1 BB1 show ?thesis  
      using CC1 CC2 CC3 tickFree_implies_front_tickFree by auto
    qed
  qed

lemma is_processT5_SYNC2: "
 sa Y t u Xa Ya.  (t,Xa)   P  (u,Ya)   Q  (sa setinterleaves ((t,u),insert tick (ev ` A))) 
  c. c  Y 
        ( t1 u1. (sa@[c]) setinterleaves ((t1,u1),insert tick (ev ` A))
        (((t1,{})   P(u1, {})   Q)((t1,{})   Q(u1, {})   P))) 
   t2 u2 Xb. (t2, Xb)   P  
                  (Yb. (u2, Yb)   Q 
                        sa setinterleaves ((t2, u2), insert tick (ev ` A)) 
                        ( Xa  Ya)  insert tick (ev ` A)  Xa  Ya  Y = 
                            (Xb  Yb)  insert tick (ev ` A)  Xb  Yb)"  
proof -
  fix sa Y t u Xa Ya
  assume A: "(t,Xa)   P  (u,Ya)   Q (sa setinterleaves ((t,u),insert tick (ev ` A)))" 
  and B: " c. c  Y 
               ( t1 u1. (sa@[c]) setinterleaves ((t1,u1),insert tick (ev ` A)) 
               (((t1,{})   P 
               (u1, {})   Q)  ((t1,{})   Q(u1, {})   P)))"
  thus "t2 u2 Xb. (t2, Xb)   P  
                   (Yb. (u2, Yb)   Q  sa setinterleaves ((t2, u2), insert tick (ev ` A)) 
                   (Xa  Ya)  insert tick (ev ` A)  Xa  Ya  Y = 
                      (Xb  Yb)  insert tick (ev ` A)  Xb  Yb)"
  proof-
    from A B obtain Y1 Y2 
               where A1: "(Y1=(Yinsert tick (ev ` A)))(Y2=(Y - insert tick (ev ` A)))" 
      by blast
    from A1 have AA1: "Y1  Y2 = Y" 
      by blast 
    from A1 have newAA: "yY1. y insert tick (ev ` A)" 
      by blast
    from A1 have newAAA: "yY2. y insert tick (ev ` A)" 
      by blast
    from B A1 have AA2: "zY1.(t@[z], {})   P  (u@[z], {})   Q" 
    proof(cases "z  Y1. (t@[z], {}) P  (u@[z], {})   Q")
      case True
      from True obtain z1 where TrA: "z1Y1(t@[z1], {}) P  (u@[z1], {})   Q" 
        by blast
      from TrA A have TrB: 
             "sa setinterleaves ((t,u),insert tick(ev ` A)); 
               z1insert tick (ev ` A)
              (sa@[z1]) setinterleaves ((t@[z1],(u@[z1])),insert tick (ev ` A))"    
      proof- 
        have a: "(rev sa) setinterleaves ((rev t,rev u),insert tick (ev ` A))"  
          using local.A doubleReverse by blast
        have b: "(z1#rev sa)  setinterleaves  ((z1#rev t,z1# rev u),insert tick (ev ` A))"  
          using TrA a newAA by auto
        show ?thesis  
          using b doubleReverse by fastforce
      qed
      then show ?thesis  
        using A1 B TrA local.A by blast  
    next
      case False
      then show ?thesis 
        by blast
    qed
    from A B A1 obtain Z1 Z2 where A2: "(Z1=Y1{z.(t@[z], {}) P})(Z2=Y1-{z.(t@[z], {}) P})" 
      by blast
    from A2 have BA: "Y1=Z1Z2" 
      by blast
    from A2 have BAA: "zZ1. (t@[z], {})   P" 
      by blast
    from A2 have BAAA: "zZ2. (u@[z], {})  Q"  
      using AA2 by blast
    from A2 BA BAA have A3: "(t, Z1)  P"   
      by (meson F_T NF_NT is_processT5_S7 local.A)  
    from A A1 have A43: "yY2. (t@[y], {})  P  (u@[y], {})  Q" 
    proof(cases "yY2. ((t@[y], {})  P)((u@[y], {})  Q)")
      case True
      from True obtain y1 where innAA: "y1Y2(((t@[y1], {})  P)((u@[y1], {})  Q))" by blast
      from innAA have innAAA: "y1 insert tick (ev ` A)"  
        using newAAA by auto
      from innAA have innAA1: 
             "sa setinterleaves ((t,u),insert tick (ev ` A)); 
               y1  insert tick (ev ` A)
               ((t@[y1], {})  P
                   (sa@[y1]) setinterleaves ((t@[y1],u),insert tick (ev ` A))) 
                      ((u@[y1], {})  Q(sa@[y1]) setinterleaves((t,u@[y1]),insert tick (ev`A)))" 
        by (simp add: addNonSync)        
      with A B innAA1 innAA show ?thesis  
        by (metis A1 DiffD1 innAAA is_processT4_empty)
    next
      case False
      then show ?thesis by blast
    qed
    from A1  A2 obtain Xbb where B1: "Xbb=(XaZ1Y2)" 
      by blast
    from A B1 A3 A43  have A5: "(t, Xbb)  P"   
      by (meson BAA is_processT5_S1)
    from A1 A2 obtain Ybb where B2: "Ybb=(YaZ2Y2)" 
      by blast
    from A B have A52: "(u, Ybb)  Q"  
      by (metis A43 B2 BAAA is_processT5_S1)   
    from A1 A2 have A61: "(Xbb  Ybb)insert tick (ev ` A)=((XaYaY1Y2)  insert tick (ev ` A))"  
      using B1 B2 by blast
    from A1 have A62: "(Y1)  insert tick (ev ` A)=Y1"  
      using inf.orderE by auto
    from A1 have A63: "(Y2)  insert tick (ev ` A)={}"  
      by (simp add: AA1 Int_commute) 
    from A61 A62 A63 have A64:"((XaYaY1Y2)insert tick(ev `A))=((XaYa)insert tick(ev `A)Y1)" 
      by (simp add: Int_Un_distrib2)
    from AA1 BA B1 B2 have A65: "(XbbYbb)((XaYa)Y) " 
      by auto  
    from AA1 BA B1 B2 have A66:"(XbbYbb)((XaYa)Y2)" 
      by auto    
    from A1 A2  have A66: "((Xa  Ya)  insert tick (ev ` A)  Xa  Ya  Y) = ((Xbb  Ybb)  
    insert tick (ev ` A)  Xbb  Ybb)"
    proof -
      have f1: "(Xa  Ya)  insert tick (ev ` A)  Xa  Ya  Y = Y  Xa  Ya  ((Xa  Ya)  
      insert tick (ev ` A)  Xbb  Ybb)"using A65 by auto
      have "Xa  Ya  Y2  Xbb  Ybb = Xbb  Ybb"
        by (meson A66 le_iff_sup)
      then have "(Xa  Ya)  insert tick (ev ` A)  Xa  Ya  Y = Xbb  Ybb  ((Xa  Ya)  
      insert tick (ev ` A)  Y1)" using f1 A1 by auto
      then show ?thesis
        using A61 A64 by force
    qed
    with A5 A52 A66 show ?thesis  
      using local.A by blast  
  qed
qed

lemma pt3: 
  "ta  𝒯 P 
    u  𝒯 Q  (s @ t) setinterleaves ((ta, u), insert tick (ev ` A))
    t u X. (t, X)   P 
                (Y. (u, Y)   Q  
                     s setinterleaves ((t, u), insert tick (ev ` A)) 
                     tick  X  tick  Y  (X  Y)  ev ` A = {}  X  Y = {})"  
proof-
  assume a1: "ta  𝒯 P"
  assume a2: "u  𝒯 Q"
  assume a3: "(s @ t) setinterleaves ((ta, u), insert tick (ev ` A))"
  have aa: "ta  𝒯 P u  𝒯 Q  (s @ t) setinterleaves ((ta, u), insert tick (ev ` A))
                t u. t  𝒯 P (u  𝒯 Q s setinterleaves ((t, u), insert tick (ev ` A)))" 
    using is_processT3_ST_pref synPrefix by blast
  thus "t u X. (t, X)   P (Y. (u, Y)   Q 
                 s setinterleaves ((t, u), insert tick (ev ` A)) 
                 tick  X  tick  Y  (X  Y)  ev ` A = {}  X  Y = {})"  
    using NF_NT a1 a2 a3 by blast
qed
  

lemma Sync_maintains_is_process:
 "is_process ({(s,R). t u X Y. (t,X)   P  (u,Y)   Q  
                                (s setinterleaves ((t,u),(ev`A)  {tick}))  
                                R = (X  Y)  ((ev`A)  {tick})  X  Y}  
              {(s,R). t u r v. front_tickFree v  (tickFree r  v=[])  
                                s = r@v  
                                (r setinterleaves ((t,u),(ev`A)  {tick}))       
                                (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)},

              {s.     t u r v. front_tickFree v  (tickFree r  v=[])  
                                s = r@v  
                                (r setinterleaves ((t,u),(ev`A)  {tick}))  
                                (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)})"
              (is "is_process(?f, ?d)") 
proof(simp only: fst_conv snd_conv Failures_def is_process_def FAILURES_def DIVERGENCES_def,
      fold FAILURES_def DIVERGENCES_def,fold Failures_def,intro conjI) 
  show "([], {})  ?f" 
    apply auto 
    by (metis Int_commute Int_empty_right Sync.si_empty1 Un_empty empty_iff insert_iff is_processT1) 
next 
  show " s X. (s, X)  ?f  front_tickFree s" 
    apply (auto simp:is_processT2 append_T_imp_tickFree front_tickFree_append D_imp_front_tickFree) 
      using ftf_Sync is_processT2 apply blast
     using D_imp_front_tickFree ftf_Sync is_processT2_TR apply blast
    using D_imp_front_tickFree ftf_Sync is_processT2_TR by blast  
next
  show "s t. (s @ t, {})  ?f  (s, {})  ?f" 
    apply auto   
        apply(drule F_T) 
        apply(drule F_T) 
  proof(goal_cases)
    case (1 s t ta u X Y)
    then show ?case 
      using pt3 by fastforce
next
  case (2 s t ta u r v)
  have aa: "front_tickFree v 
              s@t = r @ v  r setinterleaves ((ta, u), insert tick (ev ` A)) 
              t u r. r setinterleaves ((t,u),insert tick(ev `A)) 
                          (v. s=r@vfront_tickFree v 
                          ¬tickFree r  v[](t  𝒟 P 
                          u  𝒯 Q)  (t  𝒟 Q  u  𝒯 P))
              tickFree r  ta  𝒟 P  u  𝒯 Q  s<r" 
    apply(simp add: append_eq_append_conv2) 
    by (metis append_Nil2 front_tickFree_Nil front_tickFree_dw_closed le_list_def less_list_def)
  from 2(1,2,3,4,5,6,7) Sync.sym aa have a1: "s<r" by blast
  have aaa: "r setinterleaves ((ta, u), insert tick (ev ` A)) 
              tickFree r  ta  𝒟 P
              u  𝒯 Q  s<r 
              t u X. (t, X)   P  (Y. (u, Y)   Q 
                        s setinterleaves ((t, u), insert tick (ev ` A)) 
                        tick  X  tick  Y  (X  Y)  ev ` A = {}  X  Y = {})"
    apply(drule D_T) 
    apply(simp add: le_list_def less_list_def)  
    using Sync.sym pt3 by blast
  have aab: "t u X. (t, X)   P (Y. (u, Y)   Q  
                     s setinterleaves ((t, u), insert tick (ev ` A))  
                     tick  X  tick  Y  (X  Y)  ev ` A = {}  X  Y = {})" 
    using 2(1,2,3,4,5,6,7) aa aaa Sync.sym by auto
  then show ?case by auto  
next
  case (3 s t ta u r v)
  have aa: "front_tickFree v s @ t = r @ v 
            r setinterleaves ((ta, u), insert tick (ev ` A)) 
            t u r. r setinterleaves ((t, u), insert tick (ev ` A)) 
                  (v. s = r @ v front_tickFree v ¬ tickFree r  v  []  
                         (t  𝒟 P  u  𝒯 Q)  (t  𝒟 Q  u  𝒯 P)) 
            tickFree r 
            ta  𝒟 Q  u  𝒯 P  s<r"  
    apply(simp add: append_eq_append_conv2) 
    by (metis append_Nil2 front_tickFree_Nil front_tickFree_dw_closed le_list_def less_list_def)
  
  have aaa: "r setinterleaves ((ta, u), insert tick (ev ` A)) 
              tickFree r  ta  𝒟 Q  u  𝒯 P s<r
              t u X. (t, X)   P  
                         (Y. (u, Y)   Q s setinterleaves ((t, u), insert tick (ev ` A)) 
                          tick  X  tick  Y  (X  Y)  ev ` A = {}  X  Y = {})" 
    apply(drule D_T) 
    apply(simp add: le_list_def less_list_def)  
    using Sync.sym pt3 by blast
  from 3(1,2,3,4,5,6,7) Sync.sym aa have a1: "s<r"  
    by blast
  have aab: "t u X. (t, X)   P  (Y. (u, Y)   Q  
                     s setinterleaves ((t, u), insert tick (ev ` A))  
                     tick  X  tick  Y  (X  Y)  ev ` A = {}  X  Y = {})" 
    using 3(1,2,3,4,5,6,7) aa aaa Sync.sym by auto 
  then show ?case 
    by auto 
next
  case (4 s t ta u)
  from 4(3) have a1: "ta  𝒯 P"  
    by (simp add: D_T)
  then show ?case  
    using "4"(1) "4"(4) pt3 by blast  
next
  case (5 s t ta u)
  from 5(3) have a1: "ta  𝒯 Q"  
    by (simp add: D_T)
  then show ?case  
    using "5"(1) "5"(4) Sync.sym pt3 by blast
qed      
next 
  show "s X Y. (s, Y)  ?f  X  Y  (s, X)  ?f"   
    apply auto 
  proof(goal_cases)
    case (1 s X t u Xa Ya)
    have aa: "X  ((Xa  Ya)  insert tick (ev ` A)  Xa  Ya )x1 y1. x1Xa  y1Ya  
    X=((x1  y1)  insert tick (ev ` A)  x1  y1)" 
      apply(simp add: Set.subset_iff_psubset_eq) 
      apply(erule disjE) 
       defer 
       apply blast 
    proof-
      assume A: "X  (Xa  Ya)  insert tick (ev ` A)  Xa  Ya" 
      from A obtain X1 where B: "X1=((Xa  Ya)  insert tick (ev ` A)  Xa  Ya)-X" 
        by blast
      from A obtain x where C: "x=Xa-X1" 
        by blast
      from A obtain y where D: "y=Ya-X1" 
        by blast
      from A B C D have E: "X = (x  y)  insert tick (ev ` A)  x  y" 
        by blast
      thus " x1. (x1  Xa  x1 = Xa)  (y1. (y1  Ya  y1 = Ya)  X = (x1  y1)  
      insert tick (ev ` A)  x1  y1)"
        using A B C D E by (metis Un_Diff_Int inf.strict_order_iff inf_sup_absorb) 
    qed 
    then show ?case using 1(1,2,3,4,5)  
      by (meson process_charn)
  qed
 
next  
  let ?f1 = "{(s,R).  t u X Y. (t,X)   P  (u,Y)   Q  
                     (s setinterleaves ((t,u),(ev`A)  {tick}))  
                     R = (X  Y)  ((ev`A)  {tick})  X  Y}" 
  have is_processT5_SYNC3: 
            "sa X Y.(sa, X) ?f1 (c. cY(sa@[c],{})?f)(sa, XY)  ?f1" 
    apply(clarsimp) 
    apply(rule is_processT5_SYNC2[simplified]) 
     apply(auto simp:is_processT5) apply blast  
    by (metis Sync.sym Un_empty_right inf_sup_absorb inf_sup_aci(5) insert_absorb insert_not_empty)  
  show "s X Y. (s, X)  ?f  (c. c  Y  (s @ [c], {})  ?f)  (s, X  Y)  ?f"
    apply(intro allI impI, elim conjE UnE)
     apply(rule rev_subsetD)
      apply(rule is_processT5_SYNC3)
    by(auto)  
next
  show "s X. (s @ [tick], {})  ?f  (s, X - {tick})  ?f" 
    apply auto 
        apply(drule F_T) 
        apply(drule F_T)  
        using SyncWithTick_imp_NTF1 apply fastforce 
       apply(metis append_assoc append_same_eq front_tickFree_dw_closed nonTickFree_n_frontTickFree 
       non_tickFree_tick tickFree_append) 
      apply(metis butlast_append butlast_snoc front_tickFree_charn non_tickFree_tick tickFree_append 
      tickFree_implies_front_tickFree) 
     apply (metis NT_ND append_Nil2 front_tickFree_Nil is_processT3_ST is_processT9_S_swap 
     SyncWithTick_imp_NTF) 
    by (metis NT_ND append_Nil2 front_tickFree_Nil is_processT3_ST is_processT9_S_swap 
    SyncWithTick_imp_NTF)
    
next
  show "s t. s  ?d  tickFree s  front_tickFree t  s @ t  ?d" 
    apply auto
       using front_tickFree_append apply blast 
      using front_tickFree_append apply blast 
     apply blast
    by blast
next  
  show "s X. s  ?d   (s, X)  ?f"
    by blast
next  
  show "s. s @ [tick]  ?d  s  ?d"  
    apply auto
       apply (metis butlast_append butlast_snoc front_tickFree_charn non_tickFree_tick 
       tickFree_append tickFree_implies_front_tickFree)
      apply (metis butlast_append butlast_snoc front_tickFree_charn non_tickFree_tick 
      tickFree_append tickFree_implies_front_tickFree) 
     apply (metis D_T append.right_neutral front_tickFree_Nil is_processT3_ST is_processT9 
     SyncWithTick_imp_NTF) 
    by (metis D_T append.right_neutral front_tickFree_Nil is_processT3_ST is_processT9 
    SyncWithTick_imp_NTF) 
qed

lemmas  Rep_Abs_Sync[simp] = Abs_process_inverse[simplified, OF Sync_maintains_is_process]

subsection‹Projections›

lemma
  F_Sync    : " (P  A  Q) = 
                   {(s,R). t u X Y. (t,X)   P  
                                       (u,Y)   Q  
                                       s setinterleaves ((t,u),(ev`A)  {tick})  
                                       R = (X  Y)  ((ev`A)  {tick})  X  Y}  
                   {(s,R). t u r v. front_tickFree v  
                                       (tickFree r  v=[])  
                                       s = r@v  
                                       r setinterleaves ((t,u),(ev`A){tick})  
                                       (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)}"
       
       
  unfolding Sync_def 
  apply(subst Failures_def) 
  apply(simp only: Rep_Abs_Sync) 
  by(auto simp: FAILURES_def)
   

lemma
  D_Sync    : "𝒟 (P  A  Q) = 
                   {s.     t u r v. front_tickFree v  (tickFree r  v=[])  
                            s = r@v  r setinterleaves ((t,u),(ev`A)  {tick})  
                            (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)}"

  unfolding Sync_def
  apply(subst D_def)
  apply(simp only: Rep_Abs_Sync)
  by(simp add: DIVERGENCES_def)
 

lemma
  T_Sync    : "𝒯 (P  A  Q) = 
                   {s.     t u. t  𝒯 P  u  𝒯 Q  
                                 s setinterleaves ((t,u),(ev`A)  {tick})}
                   {s.     t u r v. front_tickFree v  (tickFree r  v=[])  
                                 s = r@v  r setinterleaves ((t,u),(ev`A)  {tick})  
                                 (t  𝒟 P  u  𝒯 Q  t  𝒟 Q  u  𝒯 P)}"

  unfolding Sync_def
  apply(subst Traces_def, simp only: Rep_Abs_Sync, simp add:TRACES_def FAILURES_def)
  apply auto 
   apply (meson F_T)
  using T_F by blast
  
subsection‹Syntax for Interleave and Parallel Operator ›

abbreviation Inter_syntax  ("(_|||_)" [72,73] 72)
  where "P ||| Q  (P  {}  Q)"

abbreviation Par_syntax  ("(_||_)" [74,75] 74)
  where "P || Q   (P  UNIV  Q)"

subsection‹ Continuity Rule ›

lemma mono_Sync_D1:  
"P  Q  𝒟 (Q  A  S)  𝒟 (P  A  S)"
  apply(auto simp: D_Sync)
  using le_approx1 apply blast
  using le_approx_lemma_T apply blast
   apply (metis append_Nil2 le_approx1 subsetCE tickFree_Nil tickFree_implies_front_tickFree) 
  by (metis append_Nil2 le_approx_lemma_T subsetCE tickFree_Nil tickFree_implies_front_tickFree)

lemma mono_Sync_D2:
"P  Q( s. s  𝒟 (P   A   S)  Ra (P   A   S) s = Ra (Q   A   S) s)"
  apply auto 
   apply(simp add: Ra_def D_Sync F_Sync)
   apply (metis (no_types, lifting) F_T append_Nil2 front_tickFree_Nil le_approx2)
  apply(simp add: Ra_def D_Sync F_Sync)
  apply(insert le_approx_lemma_F[of P Q] le_approx_lemma_T[of P Q]  
               le_approx1[of P Q] le_approx2T[of P Q], auto) 
      apply blast
     apply blast
    apply blast
  using front_tickFree_Nil apply blast
  using front_tickFree_Nil by blast

lemma interPrefixEmpty: "s setinterleaves ((t,[]),A)t1<ts1<s. s1 setinterleaves ((t1, []), A)"
  by (metis (no_types, lifting) Sync.sym emptyLeftProperty le_list_def nil_le2 
  order.strict_implies_order synPrefix1)

lemma interPrefix:"u1 s1. s setinterleaves((t,u),A)t1<tu1us1<ss1 setinterleaves((t1,u1),A)"
proof (induction "length t + length u" arbitrary:s t u t1 rule:nat_less_induct)
  case 1
  then show ?case 
    apply(cases t)
     apply auto[1]
    apply(cases u)   
     apply (meson interPrefixEmpty nil_le2)   
  proof- 
    fix a list aa lista 
    assume a: " m<length t + length u.  x xa. m = length x + length xa  (xb xc. u1 s1. 
    xb setinterleaves((x, xa),A)xc < x  u1  xa  s1 < xb  s1 setinterleaves ((xc, u1), A))"
    and b: "t = a # list"
    and c: "u = aa # lista"
    thus "u1 s1. s setinterleaves((t, u),A)t1<tu1 us1<ss1 setinterleaves ((t1, u1), A)"  
    proof-
      from b c have th0pre: "a=aaaa As setinterleaves ((t, u), A) 
      (tl s) setinterleaves ((list,lista), A)" by auto    
      from a obtain yu ys  
        where th0pre1: "a=aaaa A  s setinterleaves ((t, u), A) t1 < a # list  length t1>0
                         yu  lista  ys<tl s  ys setinterleaves ((tl t1, yu), A)"    
        apply (simp add: le_list_def less_list_def append_eq_Cons_conv) 
        by (metis add_less_mono b c length_Cons lessI list.sel(3) th0pre)        
      from th0pre th0pre1  b c 
      have th0pre2: "a=aa  aaA
                      s setinterleaves ((a # list, u), A)  t1<a#listlength t1>0
                      (a#ys)setinterleaves((a#tl t1, a#yu), A)a#ys<sa#yuut1=a#tl t1"   
        apply (simp add: le_list_def less_list_def  Cons_eq_append_conv)  
        by (metis append_Cons list.exhaust_sel list.inject list.sel(3))
      have th0pre3: "a=aaaaAs setinterleaves ((a # list, u), A)t1 < a # listlength t1=0
      []<s[]u [] setinterleaves ((t1, []), A)"  
        apply (simp add: le_list_def less_list_def) using c by auto
      from  th0pre2 th0pre3 c  have th0 : "a=aaaaAs setinterleaves ((a # list, u), A) 
      t1 < a # listu1u. s1<s. s1 setinterleaves ((t1, u1), A)"  by fastforce
      from b c have th1pre: "aAaa As setinterleaves ((a # list, u), A) 
      (tl s) setinterleaves ((list,aa#lista), A)" by auto
      from a obtain yu1 ys1  where th1pre1: "aAaa As setinterleaves ((a # list, u), A) 
      t1 < a # listlength t1>0yu1uys1<tl sys1 setinterleaves ((tl t1, yu1), A)"  
        apply (simp add: le_list_def less_list_def append_eq_Cons_conv)  
        by (metis add_Suc b c length_Cons lessI list.sel(3) th1pre)
      from th1pre1 have th1pre2: "aAaa A  ys1 setinterleaves ((tl t1, yu1), A)
      (a#ys1) setinterleaves ((a#tl t1, yu1), A)" apply simp  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident)
      from th1pre th1pre1  b c have th1pre3: "aAaa As setinterleaves ((a # list, u), A) 
      t1<a#listlength t1>0(a#ys1) setinterleaves ((a#tl t1, yu1), A)a#ys1<syu1ut1=a#tl t1"  
        apply (simp add: le_list_def less_list_def )  
        by (metis append_Cons list.exhaust_sel list.inject list.sel(3) th1pre2)
      have th1preEmpty: "aAaa As setinterleaves ((a # list, u), A)t1 < a # listlength t1=0
      []<s[]u [] setinterleaves ((t1, []), A)" apply (simp add: le_list_def less_list_def) 
        using c by auto
      from c have th1: "aAaa As setinterleaves ((a # list, u), A)t1 < a # list
      u1u. s1<s. s1 setinterleaves ((t1, u1), A)"   using th1pre3 th1preEmpty by fastforce
      from b c have th2pre: "aaAa As setinterleaves ((a # list, u), A) 
      (tl s) setinterleaves ((a#list,lista), A)" by auto
      from a  th2pre obtain yu2 ys2  where th2pre1: "aaAa As setinterleaves ((a # list, u), A) 
      t1 < a # listlength t1>0yu2listays2<tl sys2 setinterleaves ((t1, yu2), A)"  
        apply (simp add: le_list_def less_list_def)   
        by (metis add_Suc_right b c length_Cons lessI)    
      from th2pre1 have th2pre2: "aaAa A  ys2 setinterleaves ((t1, yu2), A)
      (aa#ys2) setinterleaves ((t1, aa#yu2), A)" apply simp  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident)
      from th2pre th2pre1  b c have th2pre3: "aaAa A s setinterleaves ((a # list, u), A) 
      t1 < a # listlength t1>0(aa#ys2) setinterleaves ((t1, aa#yu2), A)aa#ys2<saa#yu2u"  
        apply (simp add: le_list_def less_list_def )  using th2pre2 by auto
      have th2preEmpty: "aaAa As setinterleaves ((a # list, u), A)t1 < a # listlength t1=0
      []<s[]u [] setinterleaves ((t1, []), A)" apply (simp add: le_list_def less_list_def) 
        using c by auto
      from th2pre3 b c have th2: "aaAa As setinterleaves ((a # list, u), A)t1 < a # list
      u1u. s1<s. s1 setinterleaves ((t1, u1), A)"  
        using th2preEmpty by blast
      from b c have th3pre: "aaAa As setinterleaves ((a # list, u), A) 
      (tl s) setinterleaves ((a#list,lista), A)hd s=aa(tl s) setinterleaves ((list,u), A)hd s=a" 
        by auto
      from a c b th3pre obtain yu3 ys3  where th3pre1: "(aaAa As setinterleaves 
      ((a # list, u), A) t1 < a # listlength t1>0(tl s) setinterleaves ((a#list,lista), A)
      yu3listays3<tl sys3 setinterleaves((t1,yu3),A))" apply(simp add:le_list_def less_list_def) 
        by (metis (no_types, lifting) add_Suc length_Cons lessI) 
      have adsmallPrefix: "t1<a # listlength t1>0tl t1<list"  
        using less_tail by fastforce
      from a b c th3pre adsmallPrefix obtain yu30 ys30   where th3pre12: "(aaAa A
      (tl s) setinterleaves ((list,u), A)hd s=atl t1< listyu30uys30<tl s
      ys30 setinterleaves ((tl t1, yu30), A))" apply (simp add: le_list_def less_list_def)  
        by (metis (no_types, lifting) add_Suc_right length_Cons lessI)  
      have th3pre1more1: "yu3lista aa#yu3u " using c  
        by (metis le_less less_cons)
      have th3pre1more2: "aaAa As setinterleaves ((a # list, aa#lista), A) 
      (tl s) setinterleaves ((a#list,lista), A)hd s=aays3<tl s aa#ys3<s " using c 
        by (metis less_cons list.exhaust_sel list.sel(2) nil_less)
      have  th3pre1more21: "aa  A a  A  ys3<tl sys3 setinterleaves ((t1, yu3), A)  
      hd s = aa (aa # ys3) setinterleaves ((t1, aa # yu3), A)"
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident)
      from th3pre1more1 th3pre1more2 th3pre1more21 th3pre1 have th3pre1more3: "(aaAa A
      s setinterleaves ((a # list, u), A) t1 < a # listlength t1>0(tl s) setinterleaves 
      ((a#list,lista), A)hd s=aaaa#yu3uaa#ys3<s(aa#ys3) setinterleaves ((t1, aa#yu3), A))" 
        using c by blast     
      have th3pre1more32: "aaAa As setinterleaves ((a # list, aa#lista), A) 
      (tl s) setinterleaves ((list,aa#lista), A)hd s=ays30<tl s a#ys30<s " using c 
        by (metis less_cons list.exhaust_sel list.sel(2) nil_less)
      have  th3pre1more213: "aa  A a  A  ys30<tl sys30 setinterleaves ((tl t1, yu30), A)  
      hd s = a t1<a#list(a # ys30) setinterleaves ((a#tl t1, yu30), A)"  
        by (metis (mono_tags, lifting) addNonSync doubleReverse rev.simps(2) rev_rev_ident)
      from  th3pre1more32 th3pre12 th3pre1more213 have th3pre1more33: "(aaAa As setinterleaves 
      ((a # list, u), A) t1 < a # listlength t1>0(tl s) setinterleaves ((list,aa#lista), A)
      hd s=ayu30ua#ys30<s(a#ys30) setinterleaves ((t1, yu30), A))" 
        by (metis adsmallPrefix c hd_append2 le_list_def length_greater_0_conv list.exhaust_sel 
        list.sel(1) order.strict_implies_order)  
      from th3pre1more3 th3pre1more33 b c th3pre  have th3NoEmpty: "aaAa As setinterleaves 
      ((a # list, u), A)t1 < a # listlength t1>0u1u. s1<s. s1 setinterleaves ((t1, u1), A)" 
        apply (simp add: le_list_def less_list_def)  
        by (metis append.simps(2))   
      have th3preEmpty: "aaAa As setinterleaves ((a # list, u), A)t1 < a # listlength t1=0
      []<s[]u [] setinterleaves ((t1, []), A)"
        apply (simp add: le_list_def less_list_def) using c by auto    
      from th3NoEmpty th3preEmpty have th3: "aaAa As setinterleaves ((a # list, u), A)t1 < 
      a # listu1u. s1<s. s1 setinterleaves ((t1, u1), A)" 
        by blast      
      show?thesis  
        using b c th0 th1 th2 th3 by auto
    qed 
  qed  
qed

lemma mono_Sync2a:
   "rmin_elems(𝒟 (P A S))
    t u. r setinterleaves ((t, u),insert tick (ev ` A)) 
             (t  min_elems(𝒟 P)  u  𝒯 S  t  min_elems(𝒟 S)  
             u  𝒯 P  u  (𝒯 P - (𝒟 P-min_elems(𝒟 P))))" 
proof- 
  fix r
  assume A: "r  min_elems(𝒟 (P  A S))"
  thus "t u. r setinterleaves ((t, u), insert tick (ev ` A))(t  min_elems(𝒟 P)  
              u  𝒯 S  t  min_elems(𝒟 S)  u  𝒯 P  u  (𝒯 P - (𝒟 P-min_elems(𝒟 P))))" 
  proof(cases "t u r1. r1r r1 setinterleaves((t, u),insert tick (ev ` A))
                         (t  min_elems(𝒟 P))  (t  min_elems(𝒟 S))")
    case True
    from A have AA: "r  𝒟 (P  A S)"  
      using elem_min_elems by blast
    from AA obtain t1 u1 where A1: 
                   "r1r. r1 setinterleaves ((t1, u1), insert tick (ev ` A)) 
                              (t1  𝒟 P  t1  𝒟 S)" apply(simp add: D_Sync) 
                              using le_list_def by blast
    from True A1 have A2: "(t1  min_elems(𝒟 P))  (t1  min_elems(𝒟 S))"  
      by blast
    from A1 A2 min_elems5 obtain tm1 tm2 
      where tmA: "(t1𝒟 P  
                  (tm1t1tm1 min_elems(𝒟 P)))  (t1𝒟 S(tm2t1tm2 min_elems(𝒟 S)))"  
      by metis
    from A2 tmA have AB1: "(t1𝒟 Ptm1<t1)(t1𝒟 Stm2<t1)" 
      by (metis A1 order.not_eq_order_implies_strict)
    from A1 AB1 obtain um1 rm1 um2 rm2 where AB2: " (t1𝒟 Pum1u1  rm1 setinterleaves 
    ((tm1, um1),insert tick (ev ` A)))(t1𝒟 Sum2u1  rm2 setinterleaves 
    ((tm2, um2), insert tick (ev ` A)))" by (meson interPrefix)     
    from A1 A2 True tmA AB1 have A3: "(t1𝒟 Prm1<rrm1𝒟(PAS))(t1𝒟 Srm2<rrm2 𝒟(PAS))"  
      by (meson dual_order.strict_implies_order interPrefix order_trans) 
    from A3 AA have ATrue: "r  min_elems(𝒟 (P  A S))" using min_elems_def  
      using A1 by blast   
    with A ATrue show ?thesis 
      by blast 
  next
    case False
    from A have dsync: "r𝒟 (P A S)"  
      by (simp add: local.A elem_min_elems)
    from dsync obtain r1 t2 u2 
      where C: "r1r r1 setinterleaves ((t2, u2), insert tick (ev ` A)) 
               ((t2  𝒟 P  u2  𝒯 S)  (t2  𝒟 S  u2  𝒯 P))" 
               apply(simp add: D_Sync)  
               using le_list_def by blast
    from C have r1D: "r1  𝒟 (P A S)" apply(simp add: D_Sync)  
      using front_tickFree_Nil by blast
    from A C r1D have eq: "r1=r" apply(simp add: min_elems_def) 
      using le_neq_trans by blast
    from A False have minAa: "(t2  𝒟 Pu2𝒯 S)(t2  min_elems(𝒟 P))"  
    proof(cases "t2  𝒟 P u2  𝒯 S t2  min_elems(𝒟 P)")
      case True
      from True obtain t3 where inA: "t3<t2t3min_elems(𝒟 P)" 
        by (metis le_imp_less_or_eq min_elems5)
      from inA obtain r3 u3 where inA1: "u3u2r3 setinterleaves((t3,u3),insert tick(ev ` A))r3<r"  
        using C eq interPrefix by blast 
      from inA1 have inA3: "u3  𝒯 S"  
        using True is_processT3_ST_pref by blast
      from inA1 have inA2: "r3  𝒟(P A S)" apply (simp add: D_Sync)  
        using elem_min_elems front_tickFree_Nil inA inA3 by blast 
      with A eq inA1 show ?thesis 
        by(simp add: min_elems_def) 
    next
      case False
      then show ?thesis 
        by blast
    qed
    from A False have minAb1: "(t2  𝒟 Su2 𝒯 P)(t2  min_elems(𝒟 S))"  
    proof(cases "t2  𝒟 S  u2  𝒯 P t2  min_elems(𝒟 S)")
      case True
      from True obtain t3 r3 u3 where inA: "t3<t2t3min_elems(𝒟 S)" 
      and inA1: "u3u2r3 setinterleaves ((t3, u3), insert tick (ev ` A))r3<r"
        by (metis C eq interPrefix le_less min_elems5)
      from inA1 have inA3: "u3  𝒯 P"  
        using True is_processT3_ST_pref by blast
      from inA1 have inA2: "r3  𝒟 (P A S)" apply (simp add: D_Sync)  
        using elem_min_elems front_tickFree_Nil inA inA3 by blast 
      with A eq inA1 show ?thesis 
        by(simp add: min_elems_def)
    next
      case False
      then show ?thesis 
        by blast
    qed
    from A False have minAb2: "(t2  𝒟 Su2 𝒯 P)(u2  (𝒯 P-(𝒟 P-min_elems(𝒟 P))))" 
    proof(cases "t2  𝒟 S u2  𝒯 P u2 (𝒟 P-min_elems(𝒟 P))")
      case True
      from True have inAAA: "u2𝒟 Pu2min_elems(𝒟 P)" 
        by blast
      from inAAA obtain u3  where inA: "u3<u2u3min_elems(𝒟 P)"  
        by (metis le_neq_trans min_elems5) 
      from inA obtain t3 r3 where inA1: "t3t2r3 setinterleaves((t3,u3),insert tick(ev ` A))r3<r"  
        using C Sync.sym eq interPrefix by blast
      from inA1 have inA3: "u3  𝒟 Pt3  𝒯 S"  
        using D_T True elem_min_elems inA is_processT3_ST_pref by blast 
      from inA1 have inA2: "r3  𝒟 (P A S)" apply (simp add: D_Sync)  
        using Sync.sym front_tickFree_Nil inA3 by blast  
      with A inA1 inA2 show ?thesis 
        by(simp add: min_elems_def)
    next
      case False
      then show ?thesis 
        by blast
    qed
    with A C show ?thesis   
      using eq minAa minAb1 by blast  
  qed
qed
 
lemma mono_Sync_D3: 
  assumes ordered: "P  Q" 
  shows "min_elems (𝒟 (P A S))  𝒯(Q A S)" 
proof- 
  have mono_sync2b:"P  Q  r. r  min_elems(𝒟 (PAS))r  𝒯(QAS)" 
    apply(frule impI)
    apply(auto simp: mono_Sync2a) 
  proof - 
    fix r
    assume A: "P  Q"
    and B: "r  min_elems(𝒟(PAS))" 
    from B obtain t u 
      where E: "r setinterleaves ((t, u), insert tick (ev ` A))  (t  min_elems(𝒟 P)  
                u  𝒯 S  t  min_elems(𝒟 S)  u  (𝒯 P-(𝒟 P - min_elems(𝒟 P))))" 
               using mono_Sync2a  by blast
    from E have F:"(t  𝒯 Q  u  𝒯 S)  (t  𝒯 S  u  𝒯 Q)"  
      using le_approx2T le_approx3 ordered by blast     
    thus "r  𝒯 (Q A S)"  
      by (metis (no_types, lifting) E Sync.sym T_Sync UnCI Un_commute insert_is_Un mem_Collect_eq) 
  qed 
  show ?thesis 
    apply(insert ordered) 
    apply(frule mono_sync2b) 
    by blast
qed

lemma mono_D_Sync: "𝒟 (S  A  Q) = 𝒟 (Q  A  S)"
  by(auto simp: D_Sync)

lemma mono_T_Sync: "𝒯 (S  A  Q) = 𝒯 (Q  A  S)"
  apply(auto simp: T_Sync)  
  using Sync.sym by fastforce+
   

lemma mono_F_Sync: " (S  A  Q)  =  (Q  A  S) "
  apply auto  
   apply (simp add: F_Sync)
  using Sync.sym apply blast
  apply (simp add: F_Sync)
  using Sync.sym by blast

lemma mono_Ra_Sync: "Ra (S  A  Q) s = Ra (Q  A  S) s"
  apply auto
   apply (auto simp: Ra_def)
  by (auto simp: mono_F_Sync)

lemma mono_Sync[simp]     : "P  Q  (P  A  S)  (Q  A  S)"
  by(auto simp: le_approx_def mono_Sync_D1 mono_Sync_D2 mono_Sync_D3)

lemma mono_Sync_sym [simp]: "P  Q  (S  A  P)  (S  A  Q)"
  by (metis Process_eq_spec mono_D_Sync mono_F_Sync mono_Sync)

lemma chain_Sync1: "chain Y  chain (λi. Y i   A  S)"
  by(simp add: chain_def) 

lemma chain_Sync2: "chain Y  chain (λi. S   A  Y i)"
  by(simp add: chain_def)

lemma empty_setinterleaving : "[] setinterleaves ((t, u), A)  t = []"  
  by (cases t, cases u, auto, cases u, simp_all split:if_splits) 

lemma inters_fin_fund: "finite{(t, u). s setinterleaves ((t, u), A)}"
proof (induction "length s" arbitrary:s rule:nat_less_induct)
  case 1
  have A:"{(t, u). s setinterleaves((t, u), A)}  {([],[])}  
                   {(t, u). s setinterleaves ((t, u), A)  
                            ( a list. t = a#list   a  A)  u = []}  
                   {(t, u). s setinterleaves ((t, u), A)  
                            ( a list. u = a#list  a  A)  t = []}  
                   {(t, u). s setinterleaves ((t, u), A)  
                            ( a list aa lista. u = a#list  t = aa#lista)}" 
           (is "?A  {([],[])}  ?B  ?C  ?D") 
    apply (rule subsetI, safe)
          apply(simp_all add: neq_Nil_conv)   
         apply (metis Sync.si_empty2 Sync.sym empty_iff list.exhaust_sel)
        using list.exhaust_sel apply blast
       apply (metis Sync.sym emptyLeftNonSync list.exhaust_sel list.set_intros(1))    
      using list.exhaust_sel apply blast
     apply (metis emptyLeftNonSync list.exhaust_sel list.set_intros(1))
    by (metis Sync.si_empty2 Sync.sym empty_iff list.exhaust_sel)
  have a1:"?B  { ((hd s#list), [])| list. (tl s) setinterleaves ((list, []), A)  (hd s)  A}" 
  (is "?B   ?B1") by auto
  define f where a2:"f = (λa (t, (u::'a event list)). ((a::'a event)#t, ([]::'a event list)))"
  have a3:"?B1  {(hd s # list, []) |list. tl s setinterleaves ((list, []), A)} " (is "?B1   ?B2") 
    by blast
  from a1 a3 have a13:"?B  ?B2" 
    by simp
  have AA: "finite ?B" 
  proof (cases s)
    case Nil
    then show ?thesis 
      using not_finite_existsD by fastforce
  next
    case (Cons a list)
    hence aa:"finite{(t,u).(tl s) setinterleaves((t, u), A)}"using 1[THEN spec, of "length (tl s)"] 
      by (simp)
    have "{(hd s#list, [])|list. tl s setinterleaves((list,[]),A)}(λ(t, u).f(hd s)(t, u)) `{(t, u). 
    tl s setinterleaves ((t, u), A)}" using a2 by auto
    hence "finite ?B2" using finite_imageI [of "{(t, u). (tl s) setinterleaves ((t, u), A)}" 
    "λ(t, u). f (hd s) (t, u)", OF aa] using rev_finite_subset by auto 
    then show ?thesis using a13 
      by (meson rev_finite_subset)
  qed
  have a1:"?C  { ([],(hd s#list))| list. (tl s) setinterleaves (([],list), A)  (hd s)  A}" 
  (is "?C   ?C1") by auto
  define f where a2:"f = (λa ((t::'a event list), u). (([]::'a event list), (a::'a event)#u))"
  have a3:"?C1  {([],hd s # list) |list. tl s setinterleaves (([],list), A)} " (is "?C1   ?C2") 
    by blast
  from a1 a3 have a13:"?C  ?C2" 
    by simp
  have AAA:"finite ?C"
  proof (cases s)
    case Nil
    then show ?thesis 
      using not_finite_existsD by fastforce
  next
    case (Cons a list)
    hence aa:"finite {(t,u).(tl s)setinterleaves((t, u), A)}"using 1[THEN spec, of "length (tl s)"] 
      by (simp)
    have "{([], hd s # list) |list. tl s setinterleaves (([], list), A)}  (λ(t, u). 
    f (hd s) (t, u)) ` {(t, u). tl s setinterleaves ((t, u), A)}" using a2 by auto
    hence "finite ?C2" using finite_imageI [of "{(t, u). (tl s) setinterleaves ((t, u), A)}" 
    "λ(t, u). f (hd s) (t, u)", OF aa] using rev_finite_subset by auto 
    then show ?thesis using a13 
      by (meson rev_finite_subset)
  qed
  have dd0:"?D  {(a#l, aa#la)|a aa l la. s setinterleaves ((a#l, aa#la), A)}" (is "?D  ?D1")
    apply (rule subsetI, auto, simp split:if_splits) 
    by (blast, blast, metis, blast)
  have AAAA:"finite ?D" 
  proof (cases s)
    case Nil
    hence "?D  {([],[])}" 
      using empty_setinterleaving by auto
    then show ?thesis 
      using infinite_super by auto
  next
    case (Cons a list)
    hence dd1:"?D1  {(a#l, u)| l u. list setinterleaves ((l, u), A)} 
                 {(t, a#la)| t la. list setinterleaves ((t, la), A)} 
                 {(a#l, a#la)|l la. list setinterleaves ((l, la), A)}"(is "?D1  ?D2  ?D3  ?D4") 
      by (rule_tac subsetI, auto split:if_splits)
    with Cons have aa:"finite {(t,u). list setinterleaves ((t, u), A)}" 
      using 1[THEN spec, of "length list"] by (simp)
    define f where a2:"f = (λ (t, (u::'a event list)). ((a::'a event)# t, u))" 
    with Cons have "?D2  (f ` {(t, u). list setinterleaves ((t, u), A)})" 
      using a2 by auto
    hence dd2:"finite ?D2"
      using finite_imageI [of "{(t, u). list setinterleaves ((t, u), A)}" f, OF aa]
      by (meson rev_finite_subset)
    define f where a2:"f = (λ ((t::'a event list),u). (t,(a::'a event)#u))" 
    with Cons have "?D3  (f ` {(t, u). list setinterleaves ((t, u), A)})" 
      using a2 by auto
    hence dd3:"finite ?D3"       
      using finite_imageI [of "{(t, u). list setinterleaves ((t, u), A)}" f, OF aa]
      by (meson rev_finite_subset) 
    define f where a2:"f = (λ (t,u). ((a::'a event)#t,(a::'a event)#u))" 
    with Cons have "?D4  (f ` {(t, u). list setinterleaves ((t, u), A)})" 
      using a2 by auto
    hence dd4:"finite ?D4"
      using finite_imageI [of "{(t, u). list setinterleaves ((t, u), A)}" f, OF aa]
      by (meson rev_finite_subset)       
    with dd0 dd1 dd2 dd3 dd4 show ?thesis 
      by (simp add: finite_subset) 
  qed    
  from A AA AAA AAAA show ?case 
    by (simp add: finite_subset)    
qed

lemma inters_fin: "finite{(t, u, r). r setinterleaves ((t, u), insert tick (ev ` A))  
                                     (v. x = r @ v  front_tickFree v  (tickFree r  v = []))}" 
                  (is "finite ?A")
proof -
  have a:"?A(r  {r. r  x}. {a. t u. a=(t,u,r)r setinterleaves((t,u),insert tick(ev ` A))})" 
  (is "?A  (r  {r. r  x}. ?P r)")
    using le_list_def by fastforce
  have b:"(r::'a event list). finite (?P r)"
  proof(rule allI)
    fix r::"'a event list"
    define f where "f= (λ((t::'a event list), (u::'a event list)). (t,u,r))"
    hence "?P r  (f ` {(t, u). r setinterleaves ((t, u), insert tick (ev ` A) )})" 
      by auto
    then show "finite (?P r)" 
      using inters_fin_fund[of r "insert tick (ev ` A)"] finite_imageI[of "{(t, u). r setinterleaves 
      ((t, u), insert tick (ev ` A))}" f]  by (meson rev_finite_subset)   
  qed
  have "{t. t2. x = t @ t2} = {r. ra. r @ ra = x}" 
    by blast
  hence "finite {r. r  x}" using prefixes_fin[of x, simplified Let_def, THEN conjunct1] 
    by (auto simp add:le_list_def) 
  with a b show ?thesis 
    by (meson finite_UN_I infinite_super)
qed  

 
lemma limproc_Sync_D: 
  "chain Y 𝒟 (lim_proc(range Y)A S) = 𝒟(lim_proc(range(λi. Y i A S)))" 
  apply(auto simp:Process_eq_spec  F_Sync D_Sync T_Sync F_LUB D_LUB T_LUB chain_Sync1) 
      apply blast 
     apply blast 
    using front_tickFree_Nil apply blast
    using front_tickFree_Nil apply blast 
  proof - 
    fix x
    assume A: "chain Y"
    and B: " xa. t u r v. front_tickFree v  (tickFree r  v = [])  
                            x = r @ v  r setinterleaves ((t, u), insert tick (ev ` A))  
                            (t  𝒟 (Y xa)  u  𝒯 S  t  𝒟 S  u  𝒯 (Y xa))"
    thus   "t u r v. front_tickFree v  (tickFree r  v = [])  x = r @ v  
                      r setinterleaves ((t, u), insert tick (ev ` A))  
                      ((x. t  𝒟 (Y x))  u  𝒯 S  t  𝒟 S  (x. u  𝒯 (Y x)))" 
    proof(cases "t u r. r setinterleaves ((t, u), insert tick (ev ` A)) 
                          (rx  ((x. t  𝒟 (Y x))  u  𝒯 S)  
                           (t  𝒟 S  (x. u  𝒯 (Y x))))") 
      case True 
      from A obtain tryunion where Ctryy: 
                "tryunion={(t, u, r). r setinterleaves ((t, u), insert tick (ev ` A)) 
                                      (v.(x = r @ v  front_tickFree v  (tickFree r  v = [])))}" 
        by simp
      from Ctryy inters_fin have tolfin: "finite tryunion" 
        by auto
      obtain tryunion1 
        where Ctryy1: "tryunion1 = {n. (t,u, r)  tryunion.
                                         (t  𝒟 (Y n)  u  𝒯 S  t  𝒟 S  u  𝒯 (Y n))}" by simp
      from B Ctryy1 Ctryy have Ctryy3: "n. ntryunion1"  
        by blast  
      from Ctryy3 have Ctryy2: "infinite tryunion1"   
        using finite_nat_set_iff_bounded by auto  
      from Ctryy2 Ctryy1 tolfin obtain  r2 t2 u2 
        where Ee: "(t2,u2, r2)  tryunion  
                   infinite {n. (t2  𝒟 (Y n)  u2  𝒯 S  t2  𝒟 S  u2  𝒯 (Y n))}"  
        by auto
      from True Ee  Ctryy obtain x1 x2 
        where Ee1: "((t2  𝒟 (Y x1))  u2  𝒯 S)  (t2  𝒟 S   (u2  𝒯 (Y x2)))" 
        apply (simp add: le_list_def) by blast       
      from Ee Ee1 Ctryy obtain x3 
        where Ee2: "(x1x3)  (x2x3)  (t2  𝒟 (Y x3)  u2  𝒯 S  t2  𝒟 S  u2  𝒯 (Y x3))"  
        apply(simp add: infinite_nat_iff_unbounded_le)  
      proof - 
        assume a1: "r2 setinterleaves ((t2, u2), insert tick (ev ` A))  
                    (v. x = r2 @ v  front_tickFree v  (tickFree r2  v = []))  
                    ((m. nm. t2  𝒟 (Y n)  u2  𝒯 S)  
                     (m. nm. t2  𝒟 S  u2  𝒯 (Y n)))"
        assume a2: "x3. x1  x3  x2  x3(t2  𝒟 (Y x3)  u2  𝒯 S  t2  𝒟 S  u2  𝒯 (Y x3)) 
                     thesis"
        obtain nn :: "nat  nat" 
          where f3: "x0. (v1x0. t2  𝒟 S  u2  𝒯 (Y v1)) = 
                          (x0  nn x0  t2  𝒟 S  u2  𝒯 (Y (nn x0)))" by moura
        obtain nna :: "nat  nat" 
          where "x0. (v1x0. t2  𝒟 (Y v1)  u2  𝒯 S) = 
                      (x0  nna x0  t2  𝒟 (Y (nna x0))  u2  𝒯 S)" by moura
        then have f4: "(n. n  nna n  t2  𝒟 (Y (nna n))  u2  𝒯 S)  
                       (n. n  nn n  t2  𝒟 S  u2  𝒯 (Y (nn n)))" using f3 a1 by presburger
        have "(n. ¬ n  nn n  t2  𝒟 S  u2  𝒯 (Y (nn n)))  
              (nx1. x2  n  (t2  𝒟 (Y n)  
                      u2  𝒯 S  t2  𝒟 S  u2  𝒯 (Y n)))" by (metis le_cases order.trans) 
        moreover 
        { assume "n. ¬ n  nn n  t2  𝒟 S  u2  𝒯 (Y (nn n))"
          then have "n. n  nna n  t2  𝒟 (Y (nna n))  u2  𝒯 S" 
            using f4 by blast
          then have "nx1. x2  n  (t2  𝒟 (Y n)  u2  𝒯 S  t2  𝒟 S  u2  𝒯 (Y n))"
            by (metis (no_types) le_cases order.trans) 
        } 
        ultimately show ?thesis 
          using a2 by blast 
      qed 
      from A have Abb1: "n1 n2. n1n2  Y n1  Y n2" 
        by (simp add: po_class.chain_mono)
      from A Abb1 have Abb2: "n1 n2. n1>n2  t  𝒟 (Y n2)  t  𝒟 (Y n1)" 
        using le_approx1 less_imp_le_nat by blast
      from A Abb1 have Abb3: "n1 n2. n1>n2  t  𝒯 (Y n2)  t  𝒯 (Y n1)"  
        by (meson NT_ND le_approx2T less_imp_le_nat)
      from Abb2 Ee2 have Ab1: "t2  𝒟 (Y x1)t2  𝒟 (Y x3)"  
        by (meson Abb1 le_approx1 less_imp_le_nat subsetCE)
      from Abb3 have Ab2: "u2  𝒯 (Y x2)u2  𝒯 (Y x3)"  
        by (meson Abb1 Ee2 NT_ND le_approx2T less_imp_le_nat)
      from True Ee Ee1  Ee2 Ab1 Ab2 show ?thesis  
        by blast 
    next 
      case False 
      from A B False obtain t u r 
        where Bb1: "r setinterleaves ((t, u), insert tick (ev ` A))  r  x  
                    ((x. t  𝒟 (Y x))  u  𝒯 S  t  𝒟 S  (x. u  𝒯 (Y x)))"   
        by auto
      from B have Bb21: "front_tickFree x"  
        by (metis D_imp_front_tickFree append_Nil2 front_tickFree_append ftf_Sync is_processT2_TR)
      from B Bb1 have Bb2: "v. front_tickFree v  (tickFree r  v = []) x = r @ v"  
        by (metis Bb21 front_tickFree_Nil front_tickFree_mono le_list_def)  
      then show ?thesis  
        using Bb1 by blast  
    qed  
  qed  
   

lemma limproc_Sync_F_annex1: 
  " chain Y
     n. (a, b)   (Y n A S) 
     x. a  𝒟 (Y x A S) 
     t u X. (x. (t, X)   (Y x))  
                (Y. (u, Y)   S  a setinterleaves((t, u),insert tick (ev ` A))  
                b = (X  Y)  insert tick (ev ` A)  X  Y)"
proof - 
  fix a b
  assume A: "chain Y"
  assume B: "n. (a, b)   (Y n A S)"
  assume C: "x. a  𝒟 (Y x A S)"
  thus "t u X. (x. (t, X)   (Y x)) 
                (Y. (u, Y)   S  
                     a setinterleaves ((t, u), insert tick (ev ` A))  
                     b = (X  Y)  insert tick (ev ` A)  X  Y)" 
  proof- 
    from B C obtain x1 where D: "a  𝒟 (Y x1 A S)" 
      by blast
    from B D obtain t1 u1 X1 Y1 where E: 
         "a setinterleaves ((t1, u1), insert tick (ev ` A)) 
         (t1, X1)   (Y x1)  (u1, Y1)   S  
         b = (X1  Y1)  insert tick (ev ` A)  X1  Y1" 
      apply(auto simp: D_Sync F_Sync) 
      by fastforce
    from B D E have F: "t1  𝒟 (Y x1)  t1  𝒯(Y x1)" apply(auto simp: D_Sync)  
      using F_T front_tickFree_Nil apply blast  
      by (simp add: F_T)
    from F have ee: "i. (t1, X1)   (Y i)(u1, Y1)  S a setinterleaves 
    ((t1, u1), insert tick (ev ` A)) b = (X1  Y1)  insert tick (ev ` A)  X1  Y1"  
      using E chain_lemma is_processT8_S le_approx2 local.A by metis
    with A B C D E F ee  show?thesis 
      by blast 
  qed
qed

lemma limproc_Sync_F_annex2: 
 "chain Y 
   t u r. r setinterleaves ((t, u), insert tick (ev ` A)) 
      (v. a = r @ v  front_tickFree v  
           ¬ tickFree r  v  []  ((x. t  𝒟 (Y x))  u  𝒯 S)  
           (t  𝒟 S  (x. u  𝒯 (Y x))))
   x. a  𝒟(Y x  A  S)" 
  apply(auto simp: D_Sync) 
proof-
  fix a
  assume A: "t u r. r setinterleaves ((t, u), insert tick (ev ` A))  
                     (v. a = r @ v   front_tickFree v  
                          ¬ tickFree r  v  []  
                         ((x. t  𝒟 (Y x))  u  𝒯 S)  (t  𝒟 S   (x. u  𝒯 (Y x))))"
  assume B: "chain Y"
  thus "x. t u r. r setinterleaves ((t, u), insert tick (ev ` A)) 
           (v. a = r @ v   front_tickFree v  
           ¬ tickFree rv[]  (t  𝒟 (Y x)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y x)))" 
  proof- 
    from B have D: "((x. t  𝒟 (Y x))  u  𝒯 S)  (t  𝒟 S  (x. u  𝒯 (Y x)))
                      (x. ((t  𝒟 (Y x)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y x))))" 
      by (meson D_T chain_lemma le_approx1 le_approx2T subsetCE)
    from A obtain tryunion 
      where Ctryy: "tryunion={(t, u, r). r setinterleaves ((t, u), insert tick (ev ` A)) 
                    (v. a = r @ v  front_tickFree v  (tickFree r  v = []))}" 
      by simp
    from Ctryy have tolfin: "finite tryunion" 
      using inters_fin by auto 
    from B have Abb1: "n1 n2. n1n2  Y n1  Y n2"  
      by (simp add: po_class.chain_mono)
   from A Abb1 have Abb2: "n1 n2 t. n1>n2t  𝒟 (Y n2)t  𝒟 (Y n1)" 
      using le_approx1 less_imp_le_nat by blast
   from A Abb1 have Abb3: "n1 n2 t. n1>n2t  𝒯 (Y n2)t  𝒯 (Y n1)"  
      by (meson NT_ND le_approx2T less_imp_le_nat)
    from Abb2 Abb3 
    have oneIndexPre: "t u. ((x. t  𝒟 (Y x))  u  𝒯 S)  (t  𝒟 S  
                             (x. u  𝒯 (Y x))) 
                             (x. (t  𝒟 (Y x)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y x)))"
      by (meson B D_T ND_F_dir2' chain_lemma le_approx1 subsetCE)  
    from A B oneIndexPre Abb2 Abb3  
    have oneIndex: "t u r. r setinterleaves ((t, u), insert tick (ev ` A))  
                            (v. a = r @ v front_tickFree v  ¬ tickFree rv[] 
                            ( x.( (( t  𝒟 (Y x))  u  𝒯 S)  (t  𝒟 S  (u  𝒯 (Y x))))))" by blast
    define proUnion1 
      where finiUnion: "proUnion1 = {n. (t,u, r)tryunion. (((t  𝒟 (Y n)  u  𝒯 S)  
                                            (t  𝒟 S  u  𝒯 (Y n))) 
                                            (m. ( (t  𝒟 (Y m)u  𝒯 S)  
                                                   (t  𝒟 Su  𝒯 (Y m)))nm))}"
    from B 
    have finiSet1: "r t u. (t,u, r)  tryunion 
                              finite {n1.(((t  𝒟 (Y n1)u  𝒯 S)  
                                 (t𝒟 Su𝒯(Y n1)))(m1. ((t  𝒟 (Y m1) 
                                     u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y m1)))n1m1))}"  
     by (metis (no_types, lifting) infinite_nat_iff_unbounded mem_Collect_eq not_less)
   from B tolfin finiUnion oneIndex finiSet1  have finiSet: "finite proUnion1"  
     by auto   
   from finiSet obtain proMax where ann: "proMax=Max(proUnion1)"  
     by blast   
   from ann Abb2 have ann1: "numproUnion1. t. t  𝒟 (Y num)t  𝒟 (Y proMax)"  
     by (meson Abb1 Max_ge finiSet le_approx1 subsetCE)    
   from ann Abb3 have ann2: "numproUnion1.  t. t  𝒯 (Y num)t  𝒯 (Y proMax)"  
     by (meson Abb1 D_T Max_ge finiSet le_approx2T)
   from finiUnion 
   have ann3: "numproUnion1. r t u. r setinterleaves((t, u),insert tick (ev ` A))  
                                   (v. a = r @ v front_tickFree v  
                                         ¬ tickFree r  v  [] (( ((t𝒟(Y num))u  𝒯 S)  
                                         (t  𝒟 S  (u  𝒯 (Y num))))))" by auto
   obtain proUnion2 
     where ann0: "proUnion2 ={(t, u, r).n. (t, u, r)  tryunion 
                                            ((t  𝒟 (Y n)u  𝒯 S)  
                                            (t  𝒟 S  u  𝒯 (Y n)))}" by auto 
   from ann0 Ctryy finiUnion 
   have ann1: "t u r.  (t, u, r) proUnion2
                        num. numproUnion1  ((t  𝒟 (Y num)  u  𝒯 S)  
                                 (t  𝒟 S  u  𝒯 (Y num)))"    
   proof- 
     fix t u r
     assume a:  "(t, u, r) proUnion2"
     define P where PP:"P = (λnum. ((t  𝒟 (Y num)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y num))))"
     thus "num. numproUnion1 P num" 
     proof- 
       from finiUnion obtain minIndexRB where ann1preB: "minIndexRB={n. (P n)}" 
         by auto
       from B ann1preB obtain minmin where ab: "(minmin::nat) = Inf (minIndexRB)" 
         by auto
       from ann0 ann1preB PP have ann1preNoEmpty1: "minIndexRB  {}" 
         using a by blast
       from ab ann1preNoEmpty1 have ann1pre0:"minmin  minIndexRB" 
         using Inf_nat_def wellorder_Least_lemma(1) by force        
       have "minmin {n. t u r. (t,u,r)tryunion  ((t  𝒟 (Y n)  u  𝒯 S)  
                                 (t  𝒟 S  u  𝒯 (Y n)))  (m. (t  𝒟 (Y m)  
                                   u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y m))  n  m)}"  
         apply(rule CollectI,rule_tac x=t in exI,rule_tac x=u in exI,rule_tac x=r in exI,intro conjI)
            using a ann0 apply blast          
           using PP ann1pre0 ann1preB apply blast
           using PP ann1pre0 ann1preB apply blast 
          by (simp add: Inf_nat_def PP ab ann1preB wellorder_Least_lemma(2)) 
       then show ?thesis  
         using ann1pre0 ann1preB finiUnion by blast 
     qed 
   qed 
   from ann1 
   have ann12: "t u r. num.(t, u, r)  proUnion2  numproUnion1 
                             ((t  𝒟 (Y num)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y num)))" by auto
   from ann0 Ctryy 
   have ann2: "t u r. (t, u, r)  proUnion2  
                        (r setinterleaves ((t, u), insert tick (ev ` A)) 
                        (v. a = r @ v  front_tickFree v  (tickFree r  v = []))  
                        (nu1. (t  𝒟 (Y nu1)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y nu1))))" by simp 
   have ann15: "t u r. (r setinterleaves ((t, u), insert tick (ev ` A))  
                         (v. a = r @ v  front_tickFree v  (tickFree r  v = []))  
                         (nu1. (t  𝒟 (Y nu1)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y nu1)))) 
                                (t, u, r)  proUnion2"  
     using Ctryy ann0 by blast   
   from  ann12 ann15 
   have ann01: "t u r. ((r setinterleaves ((t, u), insert tick (ev ` A)) 
                        (v. a = r @ v  front_tickFree v  (tickFree r  v = []))  
                        (nu1. (t  𝒟 (Y nu1)u  𝒯 S)  
                        (t  𝒟 S  u  𝒯 (Y nu1))))
                           (numproUnion1. ((t  𝒟 (Y num)  u  𝒯 S)  
                              (t  𝒟 S  u  𝒯 (Y num)))))"    by blast  
   from ann01  
   have annhelp: "t u r. r setinterleaves ((t, u), insert tick (ev ` A)) 
                  (v. a = r @ v  front_tickFree v (tickFree r  v = [])
                  (numproUnion1.((t  𝒟 (Y num)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y num)))))"
     by (metis oneIndex)     
   from Abb1 Abb2 
   have annHelp2: "nn t u.
                      nn  proUnion1  (t  𝒟 (Y nn)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y nn)) 
                      (t  𝒟 (Y proMax)  u  𝒯 S)  (t  𝒟 S  u  𝒯 (Y proMax))" 
     by (metis Abb3 Max_ge ann finiSet le_neq_trans) 
   from  annHelp2 annhelp 
   have annHelp1: "t u r.
                       r setinterleaves ((t, u), insert tick (ev ` A)) 
                       (v. a = r @ v 
                            front_tickFree v 
                            tickFree r  v = []  (t  𝒟 (Y proMax)  u  𝒯 S)  
                                                    (t  𝒟 S  u  𝒯 (Y proMax)))" by blast       
   with A B  show ?thesis  
     by blast 
 qed 
qed

lemma limproc_Sync_F: 
 "chain Y  (lim_proc (range Y) A S) = (lim_proc (range (λi. Y i  A  S)))" 
  apply(auto simp add: Process_eq_spec D_Sync F_Sync F_LUB D_LUB T_LUB chain_Sync1) 
       apply blast 
      apply blast 
     apply blast 
    using front_tickFree_Nil apply blast
   using front_tickFree_Nil apply blast     
  proof- 
    fix a b
    assume A1: " x. (t u X. (t, X)   (Y x)  
                              (Y. (u, Y)   S  
                              a setinterleaves ((t, u), insert tick (ev ` A))  
                              b = (X  Y)  insert tick (ev ` A)  X  Y)) 
                     (t u r v. front_tickFree v  (tickFree r  v = [])   a = r @ v  
                              r setinterleaves ((t, u), insert tick (ev ` A))  
                              (t  𝒟 (Y x)  u  𝒯 S  t  𝒟 S  u  𝒯 (Y x)))"
    and B: " t u r. r setinterleaves ((t, u), insert tick (ev ` A))  
                     (v. a = r @ v   front_tickFree v  
                         ¬ tickFree r  v  []  
                         ((x. t  𝒟 (Y x))  u  𝒯 S)  (t  𝒟 S   (x. u  𝒯 (Y x))))"
    and C: "chain Y"
    thus  "t u X. (x. (t, X)   (Y x)) (Y. (u, Y)   S  a setinterleaves 
    ((t, u), insert tick (ev ` A))  b = (X  Y)  insert tick (ev ` A)  X  Y)" 
    proof (cases "m. a  𝒟(Y m  A  S)") 
      case True 
      then obtain m where "a  𝒟(Y m  A  S)" 
        by blast
      with A1 have D: "n. (a, b)  (Y n  A  S)"
        by (auto simp: F_Sync)
      with A1 B C  show ?thesis 
        apply(erule_tac x=m in allE)    
        apply(frule limproc_Sync_F_annex2) 
         apply simp 
        by(simp add: limproc_Sync_F_annex1) 
    next 
      case False
      with False have E: "n.  a  𝒟 (Y n  A  S)" 
        by blast
      with C E B show ?thesis 
        apply auto 
        apply(drule limproc_Sync_F_annex2) 
         apply blast 
        by fast 
    qed 
  qed
  
lemma cont_left_Sync : "chain Y  (( i. Y i)  A  S) = ( i. (Y i  A  S))"
  by(simp add: Process_eq_spec chain_Sync1 limproc_Sync_D limproc_Sync_F limproc_is_thelub) 
  
lemma cont_right_Sync : "chain Y  (S  A  ( i. Y i)) = ( i. (S  A  Y i))"
  by (metis (no_types, lifting) Process_eq_spec cont_left_Sync lub_eq mono_D_Sync mono_F_Sync)

lemma Sync_cont[simp]: 
assumes f:"cont f" 
and     g:"cont g"
shows     "cont (λx. (f x) A (g x))" 
proof - 
  have A : "x. cont g  cont (λy. y A (g x))" 
    apply (rule contI2, rule monofunI) 
     apply(auto) 
    by (simp add: cont_left_Sync)
  have B : "y. cont g  cont (λx. y A g x)" 
    apply(rule_tac c="(λ x. y  A x)" in cont_compose) 
     apply(rule contI2, rule monofunI) 
      apply (simp) 
     apply (simp add: cont_right_Sync) 
    by simp 
  show ?thesis using f g  
    apply(rule_tac  f="(λx. (λ f. f A g x))" in cont_apply) 
    by(auto intro:contI2 simp:A B)
qed 



end