theory Terms

imports "Nominal2_Atoms" "Nominal2_Eqvt" "Nominal2_Supp" "Abs" "Perm" "Fv" "../../Attic/Prove"

begin

atom_decl name

text {* primrec seems to be genarally faster than fun *}

section {*** lets with binding patterns ***}

datatype rtrm1 =

  rVr1 "name"

| rAp1 "rtrm1" "rtrm1"

| rLm1 "name" "rtrm1"        --"name is bound in trm1"

| rLt1 "bp" "rtrm1" "rtrm1"   --"all variables in bp are bound in the 2nd trm1"

and bp =

  BUnit

| BVr "name"

| BPr "bp" "bp"

print_theorems

(* to be given by the user *)

primrec 

  bv1

where

  "bv1 (BUnit) = {}"

| "bv1 (BVr x) = {atom x}"

| "bv1 (BPr bp1 bp2) = (bv1 bp1) \<union> (bv1 bp2)"

setup {* snd o define_raw_perms ["rtrm1", "bp"] ["Terms.rtrm1", "Terms.bp"] *}

thm permute_rtrm1_permute_bp.simps

local_setup {* 

  snd o define_fv_alpha "Terms.rtrm1"

  [[[[]], [[], []], [[(NONE, 0)], [(NONE, 0)]], [[(SOME @{term bv1}, 0)], [], [(SOME @{term bv1}, 0)]]],

  [[], [[]], [[], []]]] *}

notation

  alpha_rtrm1 ("_ \<approx>1 _" [100, 100] 100) and

  alpha_bp ("_ \<approx>1b _" [100, 100] 100)

thm alpha_rtrm1_alpha_bp.intros

thm fv_rtrm1_fv_bp.simps

local_setup {* (fn ctxt => snd (Local_Theory.note ((@{binding alpha1_inj}, []), (build_alpha_inj @{thms alpha_rtrm1_alpha_bp.intros} @{thms rtrm1.distinct rtrm1.inject bp.distinct bp.inject} @{thms alpha_rtrm1.cases alpha_bp.cases} ctxt)) ctxt)) *}

thm alpha1_inj

lemma alpha_bp_refl: "alpha_bp a a"

apply induct

apply (simp_all  add: alpha1_inj)

done

lemma alpha_bp_eq_eq: "alpha_bp a b = (a = b)"

apply rule

apply (induct a b rule: alpha_rtrm1_alpha_bp.inducts(2))

apply (simp_all add: alpha_bp_refl)

done

lemma alpha_bp_eq: "alpha_bp = (op =)"

apply (rule ext)+

apply (rule alpha_bp_eq_eq)

done

lemma bv1_eqvt[eqvt]:

  shows "(pi \<bullet> bv1 x) = bv1 (pi \<bullet> x)"

  apply (induct x)

  apply (simp_all add: atom_eqvt eqvts)

  done

lemma fv_rtrm1_eqvt[eqvt]:

    "(pi\<bullet>fv_rtrm1 t) = fv_rtrm1 (pi\<bullet>t)"

    "(pi\<bullet>fv_bp b) = fv_bp (pi\<bullet>b)"

  apply (induct t and b)

  apply (simp_all add: insert_eqvt atom_eqvt empty_eqvt union_eqvt Diff_eqvt bv1_eqvt)

  done

lemma alpha1_eqvt:

  "t \<approx>1 s \<Longrightarrow> (pi \<bullet> t) \<approx>1 (pi \<bullet> s)"

  "alpha_bp a b \<Longrightarrow> alpha_bp (pi \<bullet> a) (pi \<bullet> b)"

  apply (induct t s and a b rule: alpha_rtrm1_alpha_bp.inducts)

  apply (simp_all add:eqvts alpha1_inj)

  apply (erule exE)

  apply (rule_tac x="pi \<bullet> pia" in exI)

  apply (simp add: alpha_gen)

  apply(erule conjE)+

  apply(rule conjI)

  apply(rule_tac ?p1="- pi" in permute_eq_iff[THEN iffD1])

  apply(simp add: atom_eqvt Diff_eqvt insert_eqvt empty_eqvt fv_rtrm1_eqvt)

  apply(rule conjI)

  apply(rule_tac ?p1="- pi" in fresh_star_permute_iff[THEN iffD1])

  apply(simp add: atom_eqvt Diff_eqvt fv_rtrm1_eqvt insert_eqvt empty_eqvt)

  apply(simp add: permute_eqvt[symmetric])

  apply (erule exE)

  apply (erule exE)

  apply (rule conjI)

  apply (rule_tac x="pi \<bullet> pia" in exI)

  apply (simp add: alpha_gen)

  apply(erule conjE)+

  apply(rule conjI)

  apply(rule_tac ?p1="- pi" in permute_eq_iff[THEN iffD1])

  apply(simp add: fv_rtrm1_eqvt Diff_eqvt bv1_eqvt)

  apply(rule conjI)

  apply(rule_tac ?p1="- pi" in fresh_star_permute_iff[THEN iffD1])

  apply(simp add: atom_eqvt fv_rtrm1_eqvt Diff_eqvt bv1_eqvt)

  apply(simp add: permute_eqvt[symmetric])

  apply (rule_tac x="pi \<bullet> piaa" in exI)

  apply (simp add: alpha_gen)

  apply(erule conjE)+

  apply(rule conjI)

  apply(rule_tac ?p1="- pi" in permute_eq_iff[THEN iffD1])

  apply(simp add: fv_rtrm1_eqvt Diff_eqvt bv1_eqvt)

  apply(rule conjI)

  apply(rule_tac ?p1="- pi" in fresh_star_permute_iff[THEN iffD1])

  apply(simp add: atom_eqvt fv_rtrm1_eqvt Diff_eqvt bv1_eqvt)

  apply(simp add: permute_eqvt[symmetric])

  done

prove alpha1_reflp_aux: {* fst (build_alpha_refl_gl [@{term alpha_rtrm1}, @{term alpha_bp}]) *}

by (tactic {*

 (indtac @{thm rtrm1_bp.induct} ["x", "x"] THEN_ALL_NEW

  asm_full_simp_tac (HOL_ss addsimps @{thms alpha1_inj}) THEN_ALL_NEW

  TRY o REPEAT_ALL_NEW (CHANGED o rtac @{thm conjI}) THEN_ALL_NEW

  (rtac @{thm exI[of _ "0 :: perm"]} THEN'

  asm_full_simp_tac (HOL_ss addsimps @{thms alpha_gen fresh_star_def fresh_zero_perm permute_zero ball_triv}))

 ) 1 *})

prove alpha1_symp_aux: {* (fst o snd) (build_alpha_refl_gl [@{term alpha_rtrm1}, @{term alpha_bp}]) *}

by (tactic {*

 (rtac @{thm alpha_rtrm1_alpha_bp.induct} THEN_ALL_NEW

  asm_full_simp_tac (HOL_ss addsimps @{thms alpha1_inj}) THEN_ALL_NEW

  TRY o REPEAT_ALL_NEW (CHANGED o rtac @{thm conjI}) THEN_ALL_NEW

  asm_full_simp_tac (HOL_ss addsimps @{thms alpha1_eqvt})

 )) 1 *})

prove alpha1_transp_aux: {* (snd o snd) (build_alpha_refl_gl [@{term alpha_rtrm1}, @{term alpha_bp}]) *}

apply (rule alpha_rtrm1_alpha_bp.induct)

apply simp_all

apply (rule_tac [!] allI)

apply (rule_tac [!] impI)

apply (rotate_tac 4)

apply (erule alpha_rtrm1.cases)

apply (simp_all add: alpha1_inj)

apply (rotate_tac 2)

apply (erule alpha_rtrm1.cases)

apply (simp_all add: alpha1_inj)

(*apply (tactic {*

 (rtac @{thm alpha_rtrm1_alpha_bp.induct} THEN_ALL_NEW

  asm_full_simp_tac (HOL_ss addsimps @{thms alpha1_inj})) 1 *})*)

sorry

lemma helper: "(\<forall>x y z. R x y \<and> R y z \<longrightarrow> R x z) = (\<forall>xa ya. R xa ya \<longrightarrow> (\<forall>z. R ya z \<longrightarrow> R xa z))"

by meson

lemma alpha1_equivp:

  "equivp alpha_rtrm1"

  "equivp alpha_bp"

unfolding equivp_reflp_symp_transp reflp_def

apply (simp_all add: alpha1_reflp_aux)

unfolding symp_def

apply (simp_all add: alpha1_symp_aux)

unfolding transp_def

apply (simp_all only: helper)

apply (rule allI)+

apply (rule conjunct1[OF alpha1_transp_aux])

apply (rule allI)+

apply (rule conjunct2[OF alpha1_transp_aux])

done

quotient_type trm1 = rtrm1 / alpha_rtrm1

  by (rule alpha1_equivp(1))

local_setup {*

(fn ctxt => ctxt

 |> snd o (Quotient_Def.quotient_lift_const ("Vr1", @{term rVr1}))

 |> snd o (Quotient_Def.quotient_lift_const ("Ap1", @{term rAp1}))

 |> snd o (Quotient_Def.quotient_lift_const ("Lm1", @{term rLm1}))

 |> snd o (Quotient_Def.quotient_lift_const ("Lt1", @{term rLt1}))

 |> snd o (Quotient_Def.quotient_lift_const ("fv_trm1", @{term fv_rtrm1})))

*}

print_theorems

lemma alpha_rfv1:

  shows "t \<approx>1 s \<Longrightarrow> fv_rtrm1 t = fv_rtrm1 s"

  apply(induct rule: alpha_rtrm1_alpha_bp.inducts(1))

  apply(simp_all add: alpha_gen.simps alpha_bp_eq)

  done

lemma [quot_respect]:

 "(op = ===> alpha_rtrm1) rVr1 rVr1"

 "(alpha_rtrm1 ===> alpha_rtrm1 ===> alpha_rtrm1) rAp1 rAp1"

 "(op = ===> alpha_rtrm1 ===> alpha_rtrm1) rLm1 rLm1"

 "(op = ===> alpha_rtrm1 ===> alpha_rtrm1 ===> alpha_rtrm1) rLt1 rLt1"

apply (auto simp add: alpha1_inj alpha_bp_eq)

apply (rule_tac [!] x="0" in exI)

apply (simp_all add: alpha_gen fresh_star_def fresh_zero_perm alpha_rfv1 alpha_bp_eq)

done

lemma [quot_respect]:

  "(op = ===> alpha_rtrm1 ===> alpha_rtrm1) permute permute"

  by (simp add: alpha1_eqvt)

lemma [quot_respect]:

  "(alpha_rtrm1 ===> op =) fv_rtrm1 fv_rtrm1"

  by (simp add: alpha_rfv1)

lemmas trm1_bp_induct = rtrm1_bp.induct[quot_lifted]

lemmas trm1_bp_inducts = rtrm1_bp.inducts[quot_lifted]

instantiation trm1 and bp :: pt

begin

quotient_definition

  "permute_trm1 :: perm \<Rightarrow> trm1 \<Rightarrow> trm1"

is

  "permute :: perm \<Rightarrow> rtrm1 \<Rightarrow> rtrm1"

lemmas permute_trm1[simp] = permute_rtrm1_permute_bp.simps[quot_lifted]

instance

apply default

apply(induct_tac [!] x rule: trm1_bp_inducts(1))

apply(simp_all)

done

end

lemmas fv_trm1 = fv_rtrm1_fv_bp.simps[quot_lifted]

lemmas fv_trm1_eqvt = fv_rtrm1_eqvt[quot_lifted]

lemmas alpha1_INJ = alpha1_inj[unfolded alpha_gen, quot_lifted, folded alpha_gen]

lemma lm1_supp_pre:

  shows "(supp (atom x, t)) supports (Lm1 x t) "

apply(simp add: supports_def)

apply(fold fresh_def)

apply(simp add: fresh_Pair swap_fresh_fresh)

apply(clarify)

apply(subst swap_at_base_simps(3))

apply(simp_all add: fresh_atom)

done

lemma lt1_supp_pre:

  shows "(supp (x, t, s)) supports (Lt1 t x s) "

apply(simp add: supports_def)

apply(fold fresh_def)

apply(simp add: fresh_Pair swap_fresh_fresh)

done

lemma bp_supp: "finite (supp (bp :: bp))"

  apply (induct bp)

  apply(simp_all add: supp_def)

  apply (fold supp_def)

  apply (simp add: supp_at_base)

  apply(simp add: Collect_imp_eq)

  apply(simp add: Collect_neg_eq[symmetric])

  apply (fold supp_def)

  apply (simp)

  done

instance trm1 :: fs

apply default

apply(induct_tac x rule: trm1_bp_inducts(1))

apply(simp_all)

apply(simp add: supp_def alpha1_INJ eqvts)

apply(simp add: supp_def[symmetric] supp_at_base)

apply(simp only: supp_def alpha1_INJ eqvts permute_trm1)

apply(simp add: Collect_imp_eq Collect_neg_eq)

apply(rule supports_finite)

apply(rule lm1_supp_pre)

apply(simp add: supp_Pair supp_atom)

apply(rule supports_finite)

apply(rule lt1_supp_pre)

apply(simp add: supp_Pair supp_atom bp_supp)

done

lemma fv_eq_bv: "fv_bp bp = bv1 bp"

apply(induct bp rule: trm1_bp_inducts(2))

apply(simp_all)

done

lemma helper2: "{b. \<forall>pi. pi \<bullet> (a \<rightleftharpoons> b) \<bullet> bp \<noteq> bp} = {}"

apply auto

apply (rule_tac x="(x \<rightleftharpoons> a)" in exI)

apply auto

done

lemma supp_fv:

  "supp t = fv_trm1 t"

  "supp b = fv_bp b"

apply(induct t and b rule: trm1_bp_inducts)

apply(simp_all)

apply(simp add: supp_def permute_trm1 alpha1_INJ fv_trm1)

apply(simp only: supp_at_base[simplified supp_def])

apply(simp add: supp_def permute_trm1 alpha1_INJ fv_trm1)

apply(simp add: Collect_imp_eq Collect_neg_eq)

apply(subgoal_tac "supp (Lm1 name rtrm1) = supp (Abs {atom name} rtrm1)")

apply(simp add: supp_Abs fv_trm1)

apply(simp (no_asm) add: supp_def permute_set_eq atom_eqvt)

apply(simp add: alpha1_INJ)

apply(simp add: Abs_eq_iff)

apply(simp add: alpha_gen.simps)

apply(simp add: supp_eqvt[symmetric] fv_trm1_eqvt[symmetric])

apply(subgoal_tac "supp (Lt1 bp rtrm11 rtrm12) = supp(rtrm11) \<union> supp (Abs (bv1 bp) rtrm12)")

apply(simp add: supp_Abs fv_trm1 fv_eq_bv)

apply(simp (no_asm) add: supp_def)

apply(simp add: alpha1_INJ alpha_bp_eq)

apply(simp add: Abs_eq_iff)

apply(simp add: alpha_gen)

apply(simp add: supp_eqvt[symmetric] fv_trm1_eqvt[symmetric] bv1_eqvt fv_eq_bv)

apply(simp add: Collect_imp_eq Collect_neg_eq fresh_star_def helper2)

apply(simp (no_asm) add: supp_def permute_set_eq atom_eqvt)

apply(simp (no_asm) add: supp_def eqvts)

apply(fold supp_def)

apply(simp add: supp_at_base)

apply(simp (no_asm) add: supp_def Collect_imp_eq Collect_neg_eq)

apply(simp add: Collect_imp_eq[symmetric] Collect_neg_eq[symmetric] supp_def[symmetric])

done

lemma trm1_supp:

  "supp (Vr1 x) = {atom x}"

  "supp (Ap1 t1 t2) = supp t1 \<union> supp t2"

  "supp (Lm1 x t) = (supp t) - {atom x}"

  "supp (Lt1 b t s) = supp t \<union> (supp s - bv1 b)"

by (simp_all add: supp_fv fv_trm1 fv_eq_bv)

lemma trm1_induct_strong:

  assumes "\<And>name b. P b (Vr1 name)"

  and     "\<And>rtrm11 rtrm12 b. \<lbrakk>\<And>c. P c rtrm11; \<And>c. P c rtrm12\<rbrakk> \<Longrightarrow> P b (Ap1 rtrm11 rtrm12)"

  and     "\<And>name rtrm1 b. \<lbrakk>\<And>c. P c rtrm1; (atom name) \<sharp> b\<rbrakk> \<Longrightarrow> P b (Lm1 name rtrm1)"

  and     "\<And>bp rtrm11 rtrm12 b. \<lbrakk>\<And>c. P c rtrm11; \<And>c. P c rtrm12; bv1 bp \<sharp>* b\<rbrakk> \<Longrightarrow> P b (Lt1 bp rtrm11 rtrm12)"

  shows   "P a rtrma"

sorry

section {*** lets with single assignments ***}

datatype rtrm2 =

  rVr2 "name"

| rAp2 "rtrm2" "rtrm2"

| rLm2 "name" "rtrm2" --"bind (name) in (rtrm2)"

| rLt2 "rassign" "rtrm2" --"bind (bv2 rassign) in (rtrm2)"

and rassign =

  rAs "name" "rtrm2"

(* to be given by the user *)

primrec 

  rbv2

where

  "rbv2 (rAs x t) = {atom x}"

setup {* snd o define_raw_perms ["rtrm2", "rassign"] ["Terms.rtrm2", "Terms.rassign"] *}

local_setup {* snd o define_fv_alpha "Terms.rtrm2"

  [[[[]], [[], []], [[(NONE, 0)], [(NONE, 0)]], [[], [(SOME @{term rbv2}, 0)]]],

   [[[], []]]] *}

notation

  alpha_rtrm2 ("_ \<approx>2 _" [100, 100] 100) and

  alpha_rassign ("_ \<approx>2b _" [100, 100] 100)

thm alpha_rtrm2_alpha_rassign.intros

local_setup {* (fn ctxt => snd (Local_Theory.note ((@{binding alpha2_inj}, []), (build_alpha_inj @{thms alpha_rtrm2_alpha_rassign.intros} @{thms rtrm2.distinct rtrm2.inject rassign.distinct rassign.inject} @{thms alpha_rtrm2.cases alpha_rassign.cases} ctxt)) ctxt)) *}

thm alpha2_inj

lemma alpha2_equivp:

  "equivp alpha_rtrm2"

  "equivp alpha_rassign"

  sorry

quotient_type

  trm2 = rtrm2 / alpha_rtrm2

and

  assign = rassign / alpha_rassign

  by (auto intro: alpha2_equivp)

local_setup {*

(fn ctxt => ctxt

 |> snd o (Quotient_Def.quotient_lift_const ("Vr2", @{term rVr2}))

 |> snd o (Quotient_Def.quotient_lift_const ("Ap2", @{term rAp2}))

 |> snd o (Quotient_Def.quotient_lift_const ("Lm2", @{term rLm2}))

 |> snd o (Quotient_Def.quotient_lift_const ("Lt2", @{term rLt2}))

 |> snd o (Quotient_Def.quotient_lift_const ("As", @{term rAs}))

 |> snd o (Quotient_Def.quotient_lift_const ("fv_trm2", @{term fv_rtrm2}))

 |> snd o (Quotient_Def.quotient_lift_const ("bv2", @{term rbv2})))

*}

print_theorems

section {*** lets with many assignments ***}

datatype rtrm3 =

  rVr3 "name"

| rAp3 "rtrm3" "rtrm3"

| rLm3 "name" "rtrm3" --"bind (name) in (trm3)"

| rLt3 "rassigns" "rtrm3" --"bind (bv3 assigns) in (trm3)"

and rassigns =

  rANil

| rACons "name" "rtrm3" "rassigns"

(* to be given by the user *)

primrec 

  bv3

where

  "bv3 rANil = {}"

| "bv3 (rACons x t as) = {atom x} \<union> (bv3 as)"

setup {* snd o define_raw_perms ["rtrm3", "rassigns"] ["Terms.rtrm3", "Terms.rassigns"] *}

local_setup {* snd o define_fv_alpha "Terms.rtrm3"

  [[[[]], [[], []], [[(NONE, 0)], [(NONE, 0)]], [[], [(SOME @{term bv3}, 0)]]],

   [[], [[], [], []]]] *}

print_theorems

notation

  alpha_rtrm3 ("_ \<approx>3 _" [100, 100] 100) and

  alpha_rassigns ("_ \<approx>3a _" [100, 100] 100)

thm alpha_rtrm3_alpha_rassigns.intros

lemma alpha3_equivp:

  "equivp alpha_rtrm3"

  "equivp alpha_rassigns"

  sorry

quotient_type

  trm3 = rtrm3 / alpha_rtrm3

and

  assigns = rassigns / alpha_rassigns

  by (auto intro: alpha3_equivp)

section {*** lam with indirect list recursion ***}

datatype rtrm4 =

  rVr4 "name"

| rAp4 "rtrm4" "rtrm4 list"

| rLm4 "name" "rtrm4"  --"bind (name) in (trm)"

thm rtrm4.recs

(* there cannot be a clause for lists, as *)

(* permutations are  already defined in Nominal (also functions, options, and so on) *)

setup {* snd o define_raw_perms ["rtrm4"] ["Terms.rtrm4"] *}

(* "repairing" of the permute function *)

lemma repaired:

  fixes ts::"rtrm4 list"

  shows "permute_rtrm4_list p ts = p \<bullet> ts"

  apply(induct ts)

  apply(simp_all)

  done

thm permute_rtrm4_permute_rtrm4_list.simps

thm permute_rtrm4_permute_rtrm4_list.simps[simplified repaired]

local_setup {* snd o define_fv_alpha "Terms.rtrm4" [

  [[[]], [[], []], [[(NONE, 0)], [(NONE, 0)]]], [[], [[], []]]  ] *}

print_theorems

notation

  alpha_rtrm4 ("_ \<approx>4 _" [100, 100] 100) and

  alpha_rtrm4_list ("_ \<approx>4l _" [100, 100] 100)

thm alpha_rtrm4_alpha_rtrm4_list.intros

lemma alpha4_equivp: "equivp alpha_rtrm4" sorry

lemma alpha4list_equivp: "equivp alpha_rtrm4_list" sorry

quotient_type 

  qrtrm4 = rtrm4 / alpha_rtrm4 and

  qrtrm4list = "rtrm4 list" / alpha_rtrm4_list

  by (simp_all add: alpha4_equivp alpha4list_equivp)

datatype rtrm5 =

  rVr5 "name"

| rAp5 "rtrm5" "rtrm5"

| rLt5 "rlts" "rtrm5" --"bind (bv5 lts) in (rtrm5)"

and rlts =

  rLnil

| rLcons "name" "rtrm5" "rlts"

primrec

  rbv5

where

  "rbv5 rLnil = {}"

| "rbv5 (rLcons n t ltl) = {atom n} \<union> (rbv5 ltl)"

setup {* snd o define_raw_perms ["rtrm5", "rlts"] ["Terms.rtrm5", "Terms.rlts"] *}

print_theorems

local_setup {* snd o define_fv_alpha "Terms.rtrm5" [

  [[[]], [[], []], [[(SOME @{term rbv5}, 0)], [(SOME @{term rbv5}, 0)]]], [[], [[], [], []]]  ] *}

print_theorems

(* Alternate version with additional binding of name in rlts in rLcons *)

(*local_setup {* snd o define_fv_alpha "Terms.rtrm5" [

  [[[]], [[], []], [[(SOME @{term rbv5}, 0)], [(SOME @{term rbv5}, 0)]]], [[], [[(NONE,0)], [], [(NONE,0)]]]  ] *}

print_theorems*)