1(*  Title:      HOL/BNF_Def.thy
2    Author:     Dmitriy Traytel, TU Muenchen
3    Author:     Jasmin Blanchette, TU Muenchen
4    Copyright   2012, 2013, 2014
5
6Definition of bounded natural functors.
7*)
8
9section \<open>Definition of Bounded Natural Functors\<close>
10
11theory BNF_Def
12imports BNF_Cardinal_Arithmetic Fun_Def_Base
13keywords
14  "print_bnfs" :: diag and
15  "bnf" :: thy_goal
16begin
17
18lemma Collect_case_prodD: "x \<in> Collect (case_prod A) \<Longrightarrow> A (fst x) (snd x)"
19  by auto
20
21inductive
22   rel_sum :: "('a \<Rightarrow> 'c \<Rightarrow> bool) \<Rightarrow> ('b \<Rightarrow> 'd \<Rightarrow> bool) \<Rightarrow> 'a + 'b \<Rightarrow> 'c + 'd \<Rightarrow> bool" for R1 R2
23where
24  "R1 a c \<Longrightarrow> rel_sum R1 R2 (Inl a) (Inl c)"
25| "R2 b d \<Longrightarrow> rel_sum R1 R2 (Inr b) (Inr d)"
26
27definition
28  rel_fun :: "('a \<Rightarrow> 'c \<Rightarrow> bool) \<Rightarrow> ('b \<Rightarrow> 'd \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> 'b) \<Rightarrow> ('c \<Rightarrow> 'd) \<Rightarrow> bool"
29where
30  "rel_fun A B = (\<lambda>f g. \<forall>x y. A x y \<longrightarrow> B (f x) (g y))"
31
32lemma rel_funI [intro]:
33  assumes "\<And>x y. A x y \<Longrightarrow> B (f x) (g y)"
34  shows "rel_fun A B f g"
35  using assms by (simp add: rel_fun_def)
36
37lemma rel_funD:
38  assumes "rel_fun A B f g" and "A x y"
39  shows "B (f x) (g y)"
40  using assms by (simp add: rel_fun_def)
41
42lemma rel_fun_mono:
43  "\<lbrakk> rel_fun X A f g; \<And>x y. Y x y \<longrightarrow> X x y; \<And>x y. A x y \<Longrightarrow> B x y \<rbrakk> \<Longrightarrow> rel_fun Y B f g"
44by(simp add: rel_fun_def)
45
46lemma rel_fun_mono' [mono]:
47  "\<lbrakk> \<And>x y. Y x y \<longrightarrow> X x y; \<And>x y. A x y \<longrightarrow> B x y \<rbrakk> \<Longrightarrow> rel_fun X A f g \<longrightarrow> rel_fun Y B f g"
48by(simp add: rel_fun_def)
49
50definition rel_set :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'a set \<Rightarrow> 'b set \<Rightarrow> bool"
51  where "rel_set R = (\<lambda>A B. (\<forall>x\<in>A. \<exists>y\<in>B. R x y) \<and> (\<forall>y\<in>B. \<exists>x\<in>A. R x y))"
52
53lemma rel_setI:
54  assumes "\<And>x. x \<in> A \<Longrightarrow> \<exists>y\<in>B. R x y"
55  assumes "\<And>y. y \<in> B \<Longrightarrow> \<exists>x\<in>A. R x y"
56  shows "rel_set R A B"
57  using assms unfolding rel_set_def by simp
58
59lemma predicate2_transferD:
60   "\<lbrakk>rel_fun R1 (rel_fun R2 (=)) P Q; a \<in> A; b \<in> B; A \<subseteq> {(x, y). R1 x y}; B \<subseteq> {(x, y). R2 x y}\<rbrakk> \<Longrightarrow>
61   P (fst a) (fst b) \<longleftrightarrow> Q (snd a) (snd b)"
62  unfolding rel_fun_def by (blast dest!: Collect_case_prodD)
63
64definition collect where
65  "collect F x = (\<Union>f \<in> F. f x)"
66
67lemma fstI: "x = (y, z) \<Longrightarrow> fst x = y"
68  by simp
69
70lemma sndI: "x = (y, z) \<Longrightarrow> snd x = z"
71  by simp
72
73lemma bijI': "\<lbrakk>\<And>x y. (f x = f y) = (x = y); \<And>y. \<exists>x. y = f x\<rbrakk> \<Longrightarrow> bij f"
74  unfolding bij_def inj_on_def by auto blast
75
76(* Operator: *)
77definition "Gr A f = {(a, f a) | a. a \<in> A}"
78
79definition "Grp A f = (\<lambda>a b. b = f a \<and> a \<in> A)"
80
81definition vimage2p where
82  "vimage2p f g R = (\<lambda>x y. R (f x) (g y))"
83
84lemma collect_comp: "collect F \<circ> g = collect ((\<lambda>f. f \<circ> g) ` F)"
85  by (rule ext) (simp add: collect_def)
86
87definition convol ("\<langle>(_,/ _)\<rangle>") where
88  "\<langle>f, g\<rangle> \<equiv> \<lambda>a. (f a, g a)"
89
90lemma fst_convol: "fst \<circ> \<langle>f, g\<rangle> = f"
91  apply(rule ext)
92  unfolding convol_def by simp
93
94lemma snd_convol: "snd \<circ> \<langle>f, g\<rangle> = g"
95  apply(rule ext)
96  unfolding convol_def by simp
97
98lemma convol_mem_GrpI:
99  "x \<in> A \<Longrightarrow> \<langle>id, g\<rangle> x \<in> (Collect (case_prod (Grp A g)))"
100  unfolding convol_def Grp_def by auto
101
102definition csquare where
103  "csquare A f1 f2 p1 p2 \<longleftrightarrow> (\<forall> a \<in> A. f1 (p1 a) = f2 (p2 a))"
104
105lemma eq_alt: "(=) = Grp UNIV id"
106  unfolding Grp_def by auto
107
108lemma leq_conversepI: "R = (=) \<Longrightarrow> R \<le> R\<inverse>\<inverse>"
109  by auto
110
111lemma leq_OOI: "R = (=) \<Longrightarrow> R \<le> R OO R"
112  by auto
113
114lemma OO_Grp_alt: "(Grp A f)\<inverse>\<inverse> OO Grp A g = (\<lambda>x y. \<exists>z. z \<in> A \<and> f z = x \<and> g z = y)"
115  unfolding Grp_def by auto
116
117lemma Grp_UNIV_id: "f = id \<Longrightarrow> (Grp UNIV f)\<inverse>\<inverse> OO Grp UNIV f = Grp UNIV f"
118  unfolding Grp_def by auto
119
120lemma Grp_UNIV_idI: "x = y \<Longrightarrow> Grp UNIV id x y"
121  unfolding Grp_def by auto
122
123lemma Grp_mono: "A \<le> B \<Longrightarrow> Grp A f \<le> Grp B f"
124  unfolding Grp_def by auto
125
126lemma GrpI: "\<lbrakk>f x = y; x \<in> A\<rbrakk> \<Longrightarrow> Grp A f x y"
127  unfolding Grp_def by auto
128
129lemma GrpE: "Grp A f x y \<Longrightarrow> (\<lbrakk>f x = y; x \<in> A\<rbrakk> \<Longrightarrow> R) \<Longrightarrow> R"
130  unfolding Grp_def by auto
131
132lemma Collect_case_prod_Grp_eqD: "z \<in> Collect (case_prod (Grp A f)) \<Longrightarrow> (f \<circ> fst) z = snd z"
133  unfolding Grp_def comp_def by auto
134
135lemma Collect_case_prod_Grp_in: "z \<in> Collect (case_prod (Grp A f)) \<Longrightarrow> fst z \<in> A"
136  unfolding Grp_def comp_def by auto
137
138definition "pick_middlep P Q a c = (SOME b. P a b \<and> Q b c)"
139
140lemma pick_middlep:
141  "(P OO Q) a c \<Longrightarrow> P a (pick_middlep P Q a c) \<and> Q (pick_middlep P Q a c) c"
142  unfolding pick_middlep_def apply(rule someI_ex) by auto
143
144definition fstOp where
145  "fstOp P Q ac = (fst ac, pick_middlep P Q (fst ac) (snd ac))"
146
147definition sndOp where
148  "sndOp P Q ac = (pick_middlep P Q (fst ac) (snd ac), (snd ac))"
149
150lemma fstOp_in: "ac \<in> Collect (case_prod (P OO Q)) \<Longrightarrow> fstOp P Q ac \<in> Collect (case_prod P)"
151  unfolding fstOp_def mem_Collect_eq
152  by (subst (asm) surjective_pairing, unfold prod.case) (erule pick_middlep[THEN conjunct1])
153
154lemma fst_fstOp: "fst bc = (fst \<circ> fstOp P Q) bc"
155  unfolding comp_def fstOp_def by simp
156
157lemma snd_sndOp: "snd bc = (snd \<circ> sndOp P Q) bc"
158  unfolding comp_def sndOp_def by simp
159
160lemma sndOp_in: "ac \<in> Collect (case_prod (P OO Q)) \<Longrightarrow> sndOp P Q ac \<in> Collect (case_prod Q)"
161  unfolding sndOp_def mem_Collect_eq
162  by (subst (asm) surjective_pairing, unfold prod.case) (erule pick_middlep[THEN conjunct2])
163
164lemma csquare_fstOp_sndOp:
165  "csquare (Collect (f (P OO Q))) snd fst (fstOp P Q) (sndOp P Q)"
166  unfolding csquare_def fstOp_def sndOp_def using pick_middlep by simp
167
168lemma snd_fst_flip: "snd xy = (fst \<circ> (%(x, y). (y, x))) xy"
169  by (simp split: prod.split)
170
171lemma fst_snd_flip: "fst xy = (snd \<circ> (%(x, y). (y, x))) xy"
172  by (simp split: prod.split)
173
174lemma flip_pred: "A \<subseteq> Collect (case_prod (R \<inverse>\<inverse>)) \<Longrightarrow> (%(x, y). (y, x)) ` A \<subseteq> Collect (case_prod R)"
175  by auto
176
177lemma predicate2_eqD: "A = B \<Longrightarrow> A a b \<longleftrightarrow> B a b"
178  by simp
179
180lemma case_sum_o_inj: "case_sum f g \<circ> Inl = f" "case_sum f g \<circ> Inr = g"
181  by auto
182
183lemma map_sum_o_inj: "map_sum f g \<circ> Inl = Inl \<circ> f" "map_sum f g \<circ> Inr = Inr \<circ> g"
184  by auto
185
186lemma card_order_csum_cone_cexp_def:
187  "card_order r \<Longrightarrow> ( |A1| +c cone) ^c r = |Func UNIV (Inl ` A1 \<union> {Inr ()})|"
188  unfolding cexp_def cone_def Field_csum Field_card_of by (auto dest: Field_card_order)
189
190lemma If_the_inv_into_in_Func:
191  "\<lbrakk>inj_on g C; C \<subseteq> B \<union> {x}\<rbrakk> \<Longrightarrow>
192   (\<lambda>i. if i \<in> g ` C then the_inv_into C g i else x) \<in> Func UNIV (B \<union> {x})"
193  unfolding Func_def by (auto dest: the_inv_into_into)
194
195lemma If_the_inv_into_f_f:
196  "\<lbrakk>i \<in> C; inj_on g C\<rbrakk> \<Longrightarrow> ((\<lambda>i. if i \<in> g ` C then the_inv_into C g i else x) \<circ> g) i = id i"
197  unfolding Func_def by (auto elim: the_inv_into_f_f)
198
199lemma the_inv_f_o_f_id: "inj f \<Longrightarrow> (the_inv f \<circ> f) z = id z"
200  by (simp add: the_inv_f_f)
201
202lemma vimage2pI: "R (f x) (g y) \<Longrightarrow> vimage2p f g R x y"
203  unfolding vimage2p_def .
204
205lemma rel_fun_iff_leq_vimage2p: "(rel_fun R S) f g = (R \<le> vimage2p f g S)"
206  unfolding rel_fun_def vimage2p_def by auto
207
208lemma convol_image_vimage2p: "\<langle>f \<circ> fst, g \<circ> snd\<rangle> ` Collect (case_prod (vimage2p f g R)) \<subseteq> Collect (case_prod R)"
209  unfolding vimage2p_def convol_def by auto
210
211lemma vimage2p_Grp: "vimage2p f g P = Grp UNIV f OO P OO (Grp UNIV g)\<inverse>\<inverse>"
212  unfolding vimage2p_def Grp_def by auto
213
214lemma subst_Pair: "P x y \<Longrightarrow> a = (x, y) \<Longrightarrow> P (fst a) (snd a)"
215  by simp
216
217lemma comp_apply_eq: "f (g x) = h (k x) \<Longrightarrow> (f \<circ> g) x = (h \<circ> k) x"
218  unfolding comp_apply by assumption
219
220lemma refl_ge_eq: "(\<And>x. R x x) \<Longrightarrow> (=) \<le> R"
221  by auto
222
223lemma ge_eq_refl: "(=) \<le> R \<Longrightarrow> R x x"
224  by auto
225
226lemma reflp_eq: "reflp R = ((=) \<le> R)"
227  by (auto simp: reflp_def fun_eq_iff)
228
229lemma transp_relcompp: "transp r \<longleftrightarrow> r OO r \<le> r"
230  by (auto simp: transp_def)
231
232lemma symp_conversep: "symp R = (R\<inverse>\<inverse> \<le> R)"
233  by (auto simp: symp_def fun_eq_iff)
234
235lemma diag_imp_eq_le: "(\<And>x. x \<in> A \<Longrightarrow> R x x) \<Longrightarrow> \<forall>x y. x \<in> A \<longrightarrow> y \<in> A \<longrightarrow> x = y \<longrightarrow> R x y"
236  by blast
237
238definition eq_onp :: "('a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> bool"
239  where "eq_onp R = (\<lambda>x y. R x \<and> x = y)"
240
241lemma eq_onp_Grp: "eq_onp P = BNF_Def.Grp (Collect P) id"
242  unfolding eq_onp_def Grp_def by auto
243
244lemma eq_onp_to_eq: "eq_onp P x y \<Longrightarrow> x = y"
245  by (simp add: eq_onp_def)
246
247lemma eq_onp_top_eq_eq: "eq_onp top = (=)"
248  by (simp add: eq_onp_def)
249
250lemma eq_onp_same_args: "eq_onp P x x = P x"
251  by (auto simp add: eq_onp_def)
252
253lemma eq_onp_eqD: "eq_onp P = Q \<Longrightarrow> P x = Q x x"
254  unfolding eq_onp_def by blast
255
256lemma Ball_Collect: "Ball A P = (A \<subseteq> (Collect P))"
257  by auto
258
259lemma eq_onp_mono0: "\<forall>x\<in>A. P x \<longrightarrow> Q x \<Longrightarrow> \<forall>x\<in>A. \<forall>y\<in>A. eq_onp P x y \<longrightarrow> eq_onp Q x y"
260  unfolding eq_onp_def by auto
261
262lemma eq_onp_True: "eq_onp (\<lambda>_. True) = (=)"
263  unfolding eq_onp_def by simp
264
265lemma Ball_image_comp: "Ball (f ` A) g = Ball A (g \<circ> f)"
266  by auto
267
268lemma rel_fun_Collect_case_prodD:
269  "rel_fun A B f g \<Longrightarrow> X \<subseteq> Collect (case_prod A) \<Longrightarrow> x \<in> X \<Longrightarrow> B ((f \<circ> fst) x) ((g \<circ> snd) x)"
270  unfolding rel_fun_def by auto
271
272lemma eq_onp_mono_iff: "eq_onp P \<le> eq_onp Q \<longleftrightarrow> P \<le> Q"
273  unfolding eq_onp_def by auto
274
275ML_file "Tools/BNF/bnf_util.ML"
276ML_file "Tools/BNF/bnf_tactics.ML"
277ML_file "Tools/BNF/bnf_def_tactics.ML"
278ML_file "Tools/BNF/bnf_def.ML"
279
280end
281