theory Abs
imports "Nominal2_Atoms" "Nominal2_Eqvt" "Nominal2_Supp" "../Quotient" "../Quotient_Product"
begin
(* the next three lemmas that should be in Nominal \<dots>\<dots>must be cleaned *)
fun
alpha_gen
where
alpha_gen[simp del]:
"alpha_gen (bs, x) R f pi (cs, y) \<longleftrightarrow>
f x - bs = f y - cs \<and> (f x - bs) \<sharp>* pi \<and> R (pi \<bullet> x) y \<and> pi \<bullet> bs = cs"
notation
alpha_gen ("_ \<approx>gen _ _ _ _" [100, 100, 100, 100, 100] 100)
lemma [mono]: "R1 \<le> R2 \<Longrightarrow> alpha_gen x R1 \<le> alpha_gen x R2"
by (cases x) (auto simp add: le_fun_def le_bool_def alpha_gen.simps)
lemma alpha_gen_refl:
assumes a: "R x x"
shows "(bs, x) \<approx>gen R f 0 (bs, x)"
using a by (simp add: alpha_gen fresh_star_def fresh_zero_perm)
lemma alpha_gen_sym:
assumes a: "(bs, x) \<approx>gen R f p (cs, y)"
and b: "R (p \<bullet> x) y \<Longrightarrow> R (- p \<bullet> y) x"
shows "(cs, y) \<approx>gen R f (- p) (bs, x)"
using a b
by (auto simp add: alpha_gen fresh_star_def fresh_def supp_minus_perm)
lemma alpha_gen_trans:
assumes a: "(bs, x) \<approx>gen R f p1 (cs, y)"
and b: "(cs, y) \<approx>gen R f p2 (ds, z)"
and c: "\<lbrakk>R (p1 \<bullet> x) y; R (p2 \<bullet> y) z\<rbrakk> \<Longrightarrow> R ((p2 + p1) \<bullet> x) z"
shows "(bs, x) \<approx>gen R f (p2 + p1) (ds, z)"
using a b c
using supp_plus_perm
apply(simp add: alpha_gen fresh_star_def fresh_def)
apply(blast)
done
lemma alpha_gen_eqvt:
assumes a: "(bs, x) \<approx>gen R f q (cs, y)"
and b: "R (q \<bullet> x) y \<Longrightarrow> R (p \<bullet> (q \<bullet> x)) (p \<bullet> y)"
and c: "p \<bullet> (f x) = f (p \<bullet> x)"
and d: "p \<bullet> (f y) = f (p \<bullet> y)"
shows "(p \<bullet> bs, p \<bullet> x) \<approx>gen R f (p \<bullet> q) (p \<bullet> cs, p \<bullet> y)"
using a b
apply(simp add: alpha_gen c[symmetric] d[symmetric] Diff_eqvt[symmetric])
apply(simp add: permute_eqvt[symmetric])
apply(simp add: fresh_star_permute_iff)
apply(clarsimp)
done
lemma alpha_gen_compose_sym:
fixes pi
assumes b: "(aa, t) \<approx>gen (\<lambda>x1 x2. R x1 x2 \<and> R x2 x1) f pi (ab, s)"
and a: "\<And>pi t s. (R t s \<Longrightarrow> R (pi \<bullet> t) (pi \<bullet> s))"
shows "(ab, s) \<approx>gen R f (- pi) (aa, t)"
using b apply -
apply(simp add: alpha_gen.simps)
apply(erule conjE)+
apply(rule conjI)
apply(simp add: fresh_star_def fresh_minus_perm)
apply(subgoal_tac "R (- pi \<bullet> s) ((- pi) \<bullet> (pi \<bullet> t))")
apply simp
apply(clarify)
apply(simp)
apply(rule a)
apply assumption
done
lemma alpha_gen_compose_trans:
fixes pi pia
assumes b: "(aa, t) \<approx>gen (\<lambda>x1 x2. R x1 x2 \<and> (\<forall>x. R x2 x \<longrightarrow> R x1 x)) f pi (ab, ta)"
and c: "(ab, ta) \<approx>gen R f pia (ac, sa)"
and a: "\<And>pi t s. (R t s \<Longrightarrow> R (pi \<bullet> t) (pi \<bullet> s))"
shows "(aa, t) \<approx>gen R f (pia + pi) (ac, sa)"
using b c apply -
apply(simp add: alpha_gen.simps)
apply(erule conjE)+
apply(simp add: fresh_star_plus)
apply(drule_tac x="- pia \<bullet> sa" in spec)
apply(drule mp)
apply(rotate_tac 5)
apply(drule_tac pi="- pia" in a)
apply(simp)
apply(rotate_tac 7)
apply(drule_tac pi="pia" in a)
apply(simp)
done
lemma alpha_gen_compose_eqvt:
fixes pia
assumes b: "(g d, t) \<approx>gen (\<lambda>x1 x2. R x1 x2 \<and> R (pi \<bullet> x1) (pi \<bullet> x2)) f pia (g e, s)"
and c: "\<And>y. pi \<bullet> (g y) = g (pi \<bullet> y)"
and a: "\<And>x. pi \<bullet> (f x) = f (pi \<bullet> x)"
shows "(g (pi \<bullet> d), pi \<bullet> t) \<approx>gen R f (pi \<bullet> pia) (g (pi \<bullet> e), pi \<bullet> s)"
using b
apply -
apply(simp add: alpha_gen.simps)
apply(erule conjE)+
apply(rule conjI)
apply(rule_tac ?p1="- pi" in permute_eq_iff[THEN iffD1])
apply(simp add: a[symmetric] atom_eqvt Diff_eqvt insert_eqvt set_eqvt empty_eqvt c[symmetric])
apply(rule conjI)
apply(rule_tac ?p1="- pi" in fresh_star_permute_iff[THEN iffD1])
apply(simp add: a[symmetric] atom_eqvt Diff_eqvt insert_eqvt set_eqvt empty_eqvt c[symmetric])
apply(subst permute_eqvt[symmetric])
apply(simp)
apply(simp add: c[symmetric])
apply(subst permute_eqvt[symmetric])
apply simp
done
fun
alpha_abs
where
"alpha_abs (bs, x) (cs, y) = (\<exists>p. (bs, x) \<approx>gen (op=) supp p (cs, y))"
notation
alpha_abs ("_ \<approx>abs _")
lemma alpha_abs_swap:
assumes a1: "a \<notin> (supp x) - bs"
and a2: "b \<notin> (supp x) - bs"
shows "(bs, x) \<approx>abs ((a \<rightleftharpoons> b) \<bullet> bs, (a \<rightleftharpoons> b) \<bullet> x)"
apply(simp)
apply(rule_tac x="(a \<rightleftharpoons> b)" in exI)
unfolding alpha_gen
apply(simp)
apply(simp add: supp_eqvt[symmetric] Diff_eqvt[symmetric])
apply(simp add: swap_set_not_in[OF a1 a2])
apply(subgoal_tac "supp (a \<rightleftharpoons> b) \<subseteq> {a, b}")
using a1 a2
apply(simp add: fresh_star_def fresh_def)
apply(blast)
apply(simp add: supp_swap)
done
lemma alpha_gen_swap_fun:
assumes f_eqvt: "\<And>pi. (pi \<bullet> (f x)) = f (pi \<bullet> x)"
assumes a1: "a \<notin> (f x) - bs"
and a2: "b \<notin> (f x) - bs"
shows "\<exists>pi. (bs, x) \<approx>gen (op=) f pi ((a \<rightleftharpoons> b) \<bullet> bs, (a \<rightleftharpoons> b) \<bullet> x)"
apply(rule_tac x="(a \<rightleftharpoons> b)" in exI)
apply(simp add: alpha_gen)
apply(simp add: f_eqvt[symmetric] Diff_eqvt[symmetric])
apply(simp add: swap_set_not_in[OF a1 a2])
apply(subgoal_tac "supp (a \<rightleftharpoons> b) \<subseteq> {a, b}")
using a1 a2
apply(simp add: fresh_star_def fresh_def)
apply(blast)
apply(simp add: supp_swap)
done
fun
supp_abs_fun
where
"supp_abs_fun (bs, x) = (supp x) - bs"
lemma supp_abs_fun_lemma:
assumes a: "x \<approx>abs y"
shows "supp_abs_fun x = supp_abs_fun y"
using a
apply(induct rule: alpha_abs.induct)
apply(simp add: alpha_gen)
done
quotient_type 'a abs = "(atom set \<times> 'a::pt)" / "alpha_abs"
apply(rule equivpI)
unfolding reflp_def symp_def transp_def
apply(simp_all)
(* refl *)
apply(clarify)
apply(rule exI)
apply(rule alpha_gen_refl)
apply(simp)
(* symm *)
apply(clarify)
apply(rule exI)
apply(rule alpha_gen_sym)
apply(assumption)
apply(clarsimp)
(* trans *)
apply(clarify)
apply(rule exI)
apply(rule alpha_gen_trans)
apply(assumption)
apply(assumption)
apply(simp)
done
quotient_definition
"Abs::atom set \<Rightarrow> ('a::pt) \<Rightarrow> 'a abs"
is
"Pair::atom set \<Rightarrow> ('a::pt) \<Rightarrow> (atom set \<times> 'a)"
lemma [quot_respect]:
shows "((op =) ===> (op =) ===> alpha_abs) Pair Pair"
apply(clarsimp)
apply(rule exI)
apply(rule alpha_gen_refl)
apply(simp)
done
lemma [quot_respect]:
shows "((op =) ===> alpha_abs ===> alpha_abs) permute permute"
apply(clarsimp)
apply(rule exI)
apply(rule alpha_gen_eqvt)
apply(assumption)
apply(simp_all add: supp_eqvt)
done
lemma [quot_respect]:
shows "(alpha_abs ===> (op =)) supp_abs_fun supp_abs_fun"
apply(simp add: supp_abs_fun_lemma)
done
lemma abs_induct:
"\<lbrakk>\<And>as (x::'a::pt). P (Abs as x)\<rbrakk> \<Longrightarrow> P t"
apply(lifting prod.induct[where 'a="atom set" and 'b="'a"])
done
(* TEST case *)
lemmas abs_induct2 = prod.induct[where 'a="atom set" and 'b="'a::pt", quot_lifted]
thm abs_induct abs_induct2
instantiation abs :: (pt) pt
begin
quotient_definition
"permute_abs::perm \<Rightarrow> ('a::pt abs) \<Rightarrow> 'a abs"
is
"permute:: perm \<Rightarrow> (atom set \<times> 'a::pt) \<Rightarrow> (atom set \<times> 'a::pt)"
lemma permute_ABS [simp]:
fixes x::"'a::pt" (* ??? has to be 'a \<dots> 'b does not work *)
shows "(p \<bullet> (Abs as x)) = Abs (p \<bullet> as) (p \<bullet> x)"
by (lifting permute_prod.simps(1)[where 'a="atom set" and 'b="'a"])
instance
apply(default)
apply(induct_tac [!] x rule: abs_induct)
apply(simp_all)
done
end
quotient_definition
"supp_Abs_fun :: ('a::pt) abs \<Rightarrow> atom \<Rightarrow> bool"
is
"supp_abs_fun"
lemma supp_Abs_fun_simp:
shows "supp_Abs_fun (Abs bs x) = (supp x) - bs"
by (lifting supp_abs_fun.simps(1))
lemma supp_Abs_fun_eqvt [eqvt]:
shows "(p \<bullet> supp_Abs_fun x) = supp_Abs_fun (p \<bullet> x)"
apply(induct_tac x rule: abs_induct)
apply(simp add: supp_Abs_fun_simp supp_eqvt Diff_eqvt)
done
lemma supp_Abs_fun_fresh:
shows "a \<sharp> Abs bs x \<Longrightarrow> a \<sharp> supp_Abs_fun (Abs bs x)"
apply(rule fresh_fun_eqvt_app)
apply(simp add: eqvts_raw)
apply(simp)
done
lemma Abs_swap:
assumes a1: "a \<notin> (supp x) - bs"
and a2: "b \<notin> (supp x) - bs"
shows "(Abs bs x) = (Abs ((a \<rightleftharpoons> b) \<bullet> bs) ((a \<rightleftharpoons> b) \<bullet> x))"
using a1 a2 by (lifting alpha_abs_swap)
lemma Abs_supports:
shows "((supp x) - as) supports (Abs as x)"
unfolding supports_def
apply(clarify)
apply(simp (no_asm))
apply(subst Abs_swap[symmetric])
apply(simp_all)
done
lemma supp_Abs_subset1:
fixes x::"'a::fs"
shows "(supp x) - as \<subseteq> supp (Abs as x)"
apply(simp add: supp_conv_fresh)
apply(auto)
apply(drule_tac supp_Abs_fun_fresh)
apply(simp only: supp_Abs_fun_simp)
apply(simp add: fresh_def)
apply(simp add: supp_finite_atom_set finite_supp)
done
lemma supp_Abs_subset2:
fixes x::"'a::fs"
shows "supp (Abs as x) \<subseteq> (supp x) - as"
apply(rule supp_is_subset)
apply(rule Abs_supports)
apply(simp add: finite_supp)
done
lemma supp_Abs:
fixes x::"'a::fs"
shows "supp (Abs as x) = (supp x) - as"
apply(rule_tac subset_antisym)
apply(rule supp_Abs_subset2)
apply(rule supp_Abs_subset1)
done
instance abs :: (fs) fs
apply(default)
apply(induct_tac x rule: abs_induct)
apply(simp add: supp_Abs)
apply(simp add: finite_supp)
done
lemma Abs_fresh_iff:
fixes x::"'a::fs"
shows "a \<sharp> Abs bs x \<longleftrightarrow> a \<in> bs \<or> (a \<notin> bs \<and> a \<sharp> x)"
apply(simp add: fresh_def)
apply(simp add: supp_Abs)
apply(auto)
done
lemma Abs_eq_iff:
shows "Abs bs x = Abs cs y \<longleftrightarrow> (\<exists>p. (bs, x) \<approx>gen (op =) supp p (cs, y))"
by (lifting alpha_abs.simps(1))
(*
below is a construction site for showing that in the
single-binder case, the old and new alpha equivalence
coincide
*)
fun
alpha1
where
"alpha1 (a, x) (b, y) \<longleftrightarrow> (a = b \<and> x = y) \<or> (a \<noteq> b \<and> x = (a \<rightleftharpoons> b) \<bullet> y \<and> a \<sharp> y)"
notation
alpha1 ("_ \<approx>abs1 _")
fun
alpha2
where
"alpha2 (a, x) (b, y) \<longleftrightarrow> (\<exists>c. c \<sharp> (a,b,x,y) \<and> ((c \<rightleftharpoons> a) \<bullet> x) = ((c \<rightleftharpoons> b) \<bullet> y))"
notation
alpha2 ("_ \<approx>abs2 _")
lemma
assumes a: "(a, x) \<approx>abs1 (b, y)" "sort_of a = sort_of b"
shows "({a}, x) \<approx>abs ({b}, y)"
using a
apply(simp)
apply(erule disjE)
apply(simp)
apply(rule exI)
apply(rule alpha_gen_refl)
apply(simp)
apply(rule_tac x="(a \<rightleftharpoons> b)" in exI)
apply(simp add: alpha_gen)
apply(simp add: fresh_def)
apply(rule conjI)
apply(rule_tac ?p1="(a \<rightleftharpoons> b)" in permute_eq_iff[THEN iffD1])
apply(rule trans)
apply(simp add: Diff_eqvt supp_eqvt)
apply(subst swap_set_not_in)
back
apply(simp)
apply(simp)
apply(simp add: permute_set_eq)
apply(simp add: eqvts)
apply(rule_tac ?p1="(a \<rightleftharpoons> b)" in fresh_star_permute_iff[THEN iffD1])
apply(simp add: permute_self)
apply(simp add: Diff_eqvt supp_eqvt)
apply(simp add: permute_set_eq)
apply(subgoal_tac "supp (a \<rightleftharpoons> b) \<subseteq> {a, b}")
apply(simp add: fresh_star_def fresh_def)
apply(blast)
apply(simp add: supp_swap)
done
lemma perm_zero:
assumes a: "\<forall>x::atom. p \<bullet> x = x"
shows "p = 0"
using a
by (simp add: expand_perm_eq)
fun
add_perm
where
"add_perm [] = 0"
| "add_perm ((a, b) # xs) = (a \<rightleftharpoons> b) + add_perm xs"
fun
elem_perm
where
"elem_perm [] = {}"
| "elem_perm ((a, b) # xs) = {a, b} \<union> elem_perm xs"
lemma add_perm_apend:
shows "add_perm (xs @ ys) = add_perm xs + add_perm ys"
apply(induct xs arbitrary: ys)
apply(auto simp add: add_assoc)
done
lemma perm_list_exists:
fixes p::perm
shows "\<exists>xs. p = add_perm xs \<and> supp xs \<subseteq> supp p"
apply(induct p taking: "\<lambda>p::perm. card (supp p)" rule: measure_induct)
apply(rename_tac p)
apply(case_tac "supp p = {}")
apply(simp)
apply(simp add: supp_perm)
apply(drule perm_zero)
apply(simp)
apply(rule_tac x="[]" in exI)
apply(simp add: supp_Nil)
apply(subgoal_tac "\<exists>x. x \<in> supp p")
defer
apply(auto)[1]
apply(erule exE)
apply(drule_tac x="p + (((- p) \<bullet> x) \<rightleftharpoons> x)" in spec)
apply(drule mp)
defer
apply(erule exE)
apply(rule_tac x="xs @ [((- p) \<bullet> x, x)]" in exI)
apply(simp add: add_perm_apend)
apply(erule conjE)
apply(drule sym)
apply(simp)
apply(simp add: expand_perm_eq)
apply(simp add: supp_append)
apply(simp add: supp_perm supp_Cons supp_Nil supp_Pair supp_atom)
apply(rule conjI)
prefer 2
apply(auto)[1]
apply (metis left_minus minus_unique permute_atom_def_raw permute_minus_cancel(2))
defer
apply(rule psubset_card_mono)
apply(simp add: finite_supp)
apply(rule psubsetI)
defer
apply(subgoal_tac "x \<notin> supp (p + (- p \<bullet> x \<rightleftharpoons> x))")
apply(blast)
apply(simp add: supp_perm)
defer
apply(auto simp add: supp_perm)[1]
apply(case_tac "x = xa")
apply(simp)
apply(case_tac "((- p) \<bullet> x) = xa")
apply(simp)
apply(case_tac "sort_of xa = sort_of x")
apply(simp)
apply(auto)[1]
apply(simp)
apply(simp)
apply(subgoal_tac "{a. p \<bullet> (- p \<bullet> x \<rightleftharpoons> x) \<bullet> a \<noteq> a} \<subseteq> {a. p \<bullet> a \<noteq> a}")
apply(blast)
apply(auto simp add: supp_perm)[1]
apply(case_tac "x = xa")
apply(simp)
apply(case_tac "((- p) \<bullet> x) = xa")
apply(simp)
apply(case_tac "sort_of xa = sort_of x")
apply(simp)
apply(auto)[1]
apply(simp)
apply(simp)
done
lemma tt0:
fixes p::perm
shows "(supp x) \<sharp>* p \<Longrightarrow> \<forall>a \<in> supp p. a \<sharp> x"
apply(auto simp add: fresh_star_def supp_perm fresh_def)
done
lemma uu0:
shows "(\<forall>a \<in> elem_perm xs. a \<sharp> x) \<Longrightarrow> (add_perm xs \<bullet> x) = x"
apply(induct xs rule: add_perm.induct)
apply(simp)
apply(simp add: swap_fresh_fresh)
done
lemma yy0:
fixes xs::"(atom \<times> atom) list"
shows "supp xs = elem_perm xs"
apply(induct xs rule: elem_perm.induct)
apply(auto simp add: supp_Nil supp_Cons supp_Pair supp_atom)
done
lemma tt1:
shows "(supp x) \<sharp>* p \<Longrightarrow> p \<bullet> x = x"
apply(drule tt0)
apply(subgoal_tac "\<exists>xs. p = add_perm xs \<and> supp xs \<subseteq> supp p")
prefer 2
apply(rule perm_list_exists)
apply(erule exE)
apply(simp only: yy0)
apply(rule uu0)
apply(auto)
done
lemma perm_induct_test:
fixes P :: "perm => bool"
assumes fin: "finite (supp p)"
assumes zero: "P 0"
assumes swap: "\<And>a b. \<lbrakk>sort_of a = sort_of b; a \<noteq> b\<rbrakk> \<Longrightarrow> P (a \<rightleftharpoons> b)"
assumes plus: "\<And>p1 p2. \<lbrakk>supp p1 \<inter> supp p2 = {}; P p1; P p2\<rbrakk> \<Longrightarrow> P (p1 + p2)"
shows "P p"
using fin
apply(induct F\<equiv>"supp p" arbitrary: p rule: finite_induct)
apply(simp add: supp_perm)
apply(drule perm_zero)
apply(simp add: zero)
apply(rotate_tac 3)
oops
lemma yy:
assumes "S1 - {x} = S2 - {x}" "x \<in> S1" "x \<in> S2"
shows "S1 = S2"
using assms
apply (metis insert_Diff_single insert_absorb)
done
lemma permute_boolI:
fixes P::"bool"
shows "p \<bullet> P \<Longrightarrow> P"
apply(simp add: permute_bool_def)
done
lemma permute_boolE:
fixes P::"bool"
shows "P \<Longrightarrow> p \<bullet> P"
apply(simp add: permute_bool_def)
done
lemma kk:
assumes a: "p \<bullet> x = y"
shows "\<forall>a \<in> supp x. (p \<bullet> a) \<in> supp y"
using a
apply(auto)
apply(rule_tac p="- p" in permute_boolI)
apply(simp add: mem_eqvt supp_eqvt)
done
lemma ww:
assumes "a \<notin> supp x" "b \<in> supp x" "a \<noteq> b" "sort_of a = sort_of b"
shows "((a \<rightleftharpoons> b) \<bullet> x) \<noteq> x"
apply(subgoal_tac "(supp x) supports x")
apply(simp add: supports_def)
using assms
apply -
apply(drule_tac x="a" in spec)
defer
apply(rule supp_supports)
apply(auto)
apply(rotate_tac 1)
apply(drule_tac p="(a \<rightleftharpoons> b)" in permute_boolE)
apply(simp add: mem_eqvt supp_eqvt)
done
lemma alpha_abs_sym:
assumes a: "({a}, x) \<approx>abs ({b}, y)"
shows "({b}, y) \<approx>abs ({a}, x)"
using a
apply(simp)
apply(erule exE)
apply(rule_tac x="- p" in exI)
apply(simp add: alpha_gen)
apply(simp add: fresh_star_def fresh_minus_perm)
apply (metis permute_minus_cancel(2))
done
lemma alpha_abs_trans:
assumes a: "({a1}, x1) \<approx>abs ({a2}, x2)"
assumes b: "({a2}, x2) \<approx>abs ({a3}, x3)"
shows "({a1}, x1) \<approx>abs ({a3}, x3)"
using a b
apply(simp)
apply(erule exE)+
apply(rule_tac x="pa + p" in exI)
apply(simp add: alpha_gen)
apply(simp add: fresh_star_def fresh_plus_perm)
done
lemma alpha_equal:
assumes a: "({a}, x) \<approx>abs ({a}, y)"
shows "(a, x) \<approx>abs1 (a, y)"
using a
apply(simp)
apply(erule exE)
apply(simp add: alpha_gen)
apply(erule conjE)+
apply(case_tac "a \<notin> supp x")
apply(simp)
apply(subgoal_tac "supp x \<sharp>* p")
apply(drule tt1)
apply(simp)
apply(simp)
apply(simp)
apply(case_tac "a \<notin> supp y")
apply(simp)
apply(drule tt1)
apply(clarify)
apply(simp (no_asm_use))
apply(simp)
apply(simp)
apply(drule yy)
apply(simp)
apply(simp)
apply(simp)
apply(case_tac "a \<sharp> p")
apply(subgoal_tac "supp y \<sharp>* p")
apply(drule tt1)
apply(clarify)
apply(simp (no_asm_use))
apply(metis)
apply(auto simp add: fresh_star_def)[1]
apply(frule_tac kk)
apply(drule_tac x="a" in bspec)
apply(simp)
apply(simp add: fresh_def)
apply(simp add: supp_perm)
apply(subgoal_tac "((p \<bullet> a) \<sharp> p)")
apply(simp add: fresh_def supp_perm)
apply(simp add: fresh_star_def)
done
lemma alpha_unequal:
assumes a: "({a}, x) \<approx>abs ({b}, y)" "sort_of a = sort_of b" "a \<noteq> b"
shows "(a, x) \<approx>abs1 (b, y)"
using a
apply -
apply(subgoal_tac "a \<notin> supp x - {a}")
apply(subgoal_tac "b \<notin> supp x - {a}")
defer
apply(simp add: alpha_gen)
apply(simp)
apply(drule_tac alpha_abs_swap)
apply(assumption)
apply(simp only: insert_eqvt empty_eqvt swap_atom_simps)
apply(drule alpha_abs_sym)
apply(rotate_tac 4)
apply(drule_tac alpha_abs_trans)
apply(assumption)
apply(drule alpha_equal)
apply(simp)
apply(rule_tac p="(a \<rightleftharpoons> b)" in permute_boolI)
apply(simp add: fresh_eqvt)
apply(simp add: fresh_def)
done
lemma alpha_new_old:
assumes a: "({a}, x) \<approx>abs ({b}, y)" "sort_of a = sort_of b"
shows "(a, x) \<approx>abs1 (b, y)"
using a
apply(case_tac "a=b")
apply(simp only: alpha_equal)
apply(drule alpha_unequal)
apply(simp)
apply(simp)
apply(simp)
done
fun
distinct_perms
where
"distinct_perms [] = True"
| "distinct_perms (p # ps) = (supp p \<inter> supp ps = {} \<and> distinct_perms ps)"
(* support of concrete atom sets *)
lemma atom_eqvt_raw:
fixes p::"perm"
shows "(p \<bullet> atom) = atom"
by (simp add: expand_fun_eq permute_fun_def atom_eqvt)
lemma atom_image_cong:
shows "(atom ` X = atom ` Y) = (X = Y)"
apply(rule inj_image_eq_iff)
apply(simp add: inj_on_def)
done
lemma supp_atom_image:
fixes as::"'a::at_base set"
shows "supp (atom ` as) = supp as"
apply(simp add: supp_def)
apply(simp add: image_eqvt)
apply(simp add: atom_eqvt_raw)
apply(simp add: atom_image_cong)
done
lemma swap_atom_image_fresh: "\<lbrakk>a \<sharp> atom ` (fn :: ('a :: at_base set)); b \<sharp> atom ` fn\<rbrakk> \<Longrightarrow> (a \<rightleftharpoons> b) \<bullet> fn = fn"
apply (simp add: fresh_def)
apply (simp add: supp_atom_image)
apply (fold fresh_def)
apply (simp add: swap_fresh_fresh)
done
end