1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 (******************* SETS OVER TYPES *****************)
17 include "logic/connectives.ma".
19 nrecord powerclass (A: Type[0]) : Type[1] ≝ { mem: A → CProp[0] }.
21 interpretation "mem" 'mem a S = (mem ? S a).
22 interpretation "powerclass" 'powerset A = (powerclass A).
23 interpretation "subset construction" 'subset \eta.x = (mk_powerclass ? x).
25 ndefinition subseteq ≝ λA.λU,V.∀a:A. a ∈ U → a ∈ V.
26 interpretation "subseteq" 'subseteq U V = (subseteq ? U V).
28 ndefinition overlaps ≝ λA.λU,V.∃x:A.x ∈ U ∧ x ∈ V.
29 interpretation "overlaps" 'overlaps U V = (overlaps ? U V).
31 ndefinition intersect ≝ λA.λU,V:Ω^A.{ x | x ∈ U ∧ x ∈ V }.
32 interpretation "intersect" 'intersects U V = (intersect ? U V).
34 ndefinition union ≝ λA.λU,V:Ω^A.{ x | x ∈ U ∨ x ∈ V }.
35 interpretation "union" 'union U V = (union ? U V).
37 ndefinition big_union ≝ λA,B.λT:Ω^A.λf:A → Ω^B.{ x | ∃i. i ∈ T ∧ x ∈ f i }.
39 ndefinition big_intersection ≝ λA,B.λT:Ω^A.λf:A → Ω^B.{ x | ∀i. i ∈ T → x ∈ f i }.
41 ndefinition full_set: ∀A. Ω^A ≝ λA.{ x | True }.
43 nlemma subseteq_refl: ∀A.∀S: Ω^A. S ⊆ S.
46 nlemma subseteq_trans: ∀A.∀S,T,U: Ω^A. S ⊆ T → T ⊆ U → S ⊆ U.
49 include "properties/relations1.ma".
51 ndefinition seteq: ∀A. equivalence_relation1 (Ω^A).
53 [ napply (λS,S'. S ⊆ S' ∧ S' ⊆ S)
56 | #S; #T; #U; *; #H1; #H2; *; /4/]
59 include "sets/setoids1.ma".
61 (* this has to be declared here, so that it is combined with carr *)
62 ncoercion full_set : ∀A:Type[0]. Ω^A ≝ full_set on A: Type[0] to (Ω^?).
64 ndefinition powerclass_setoid: Type[0] → setoid1.
68 include "hints_declaration.ma".
70 alias symbol "hint_decl" = "hint_decl_Type2".
71 unification hint 0 ≔ A ⊢ carr1 (mk_setoid1 (Ω^A) (eq1 (powerclass_setoid A))) ≡ Ω^A.
73 (************ SETS OVER SETOIDS ********************)
75 include "logic/cprop.ma".
77 nrecord ext_powerclass (A: setoid) : Type[1] ≝
78 { ext_carr:> Ω^A; (* qui pc viene dichiarato con un target preciso...
79 forse lo si vorrebbe dichiarato con un target più lasco
80 ma la sintassi :> non lo supporta *)
81 ext_prop: ∀x,x':A. x=x' → (x ∈ ext_carr) = (x' ∈ ext_carr)
84 notation > "𝛀 ^ term 90 A" non associative with precedence 70
85 for @{ 'ext_powerclass $A }.
87 notation < "Ω term 90 A \atop ≈" non associative with precedence 90
88 for @{ 'ext_powerclass $A }.
90 interpretation "extensional powerclass" 'ext_powerclass a = (ext_powerclass a).
92 ndefinition Full_set: ∀A. 𝛀^A.
93 #A; @[ napply A | #x; #x'; #H; napply refl1]
95 ncoercion Full_set: ∀A. ext_powerclass A ≝ Full_set on A: setoid to ext_powerclass ?.
97 ndefinition ext_seteq: ∀A. equivalence_relation1 (𝛀^A).
98 #A; @ [ napply (λS,S'. S = S') ] /2/.
101 ndefinition ext_powerclass_setoid: setoid → setoid1.
105 unification hint 0 ≔ A;
106 R ≟ (mk_setoid1 (𝛀^A) (eq1 (ext_powerclass_setoid A)))
107 (* ----------------------------------------------------- *) ⊢
108 carr1 R ≡ ext_powerclass A.
111 interpretation "prop21 mem" 'prop2 l r = (prop21 (setoid1_of_setoid ?) (ext_powerclass_setoid ?) ? ? ???? l r).
115 ncoercion ext_carr' : ∀A.∀x:ext_powerclass_setoid A. Ω^A ≝ ext_carr
116 on _x : (carr1 (ext_powerclass_setoid ?)) to (Ω^?).
119 nlemma mem_ext_powerclass_setoid_is_morph:
120 ∀A. unary_morphism1 (setoid1_of_setoid A) (unary_morphism1_setoid1 (ext_powerclass_setoid A) CPROP).
121 #A; napply (mk_binary_morphism1 … (λx:setoid1_of_setoid A.λS: 𝛀^A. x ∈ S));
122 #a; #a'; #b; #b'; #Ha; *; #Hb1; #Hb2; @; #H
123 [ napply (. (ext_prop … Ha^-1)) | napply (. (ext_prop … Ha)) ] /2/.
126 unification hint 0 ≔ AA, x, S;
129 TT ≟ (mk_unary_morphism1 …
130 (λx:setoid1_of_setoid ?.
132 (λS:ext_powerclass_setoid ?. x ∈ S)
133 (prop11 … (mem_ext_powerclass_setoid_is_morph AA x)))
134 (prop11 … (mem_ext_powerclass_setoid_is_morph AA))),
135 XX ≟ (ext_powerclass_setoid AA)
136 (*-------------------------------------*) ⊢
137 fun11 (setoid1_of_setoid AA)
138 (unary_morphism1_setoid1 XX CPROP) TT x S
141 nlemma subseteq_is_morph: ∀A. unary_morphism1 (ext_powerclass_setoid A)
142 (unary_morphism1_setoid1 (ext_powerclass_setoid A) CPROP).
143 #A; napply (mk_binary_morphism1 … (λS,S':𝛀^A. S ⊆ S'));
144 #a; #a'; #b; #b'; *; #H1; #H2; *; /5/ by mk_iff, sym1, subseteq_trans;
147 alias symbol "hint_decl" (instance 1) = "hint_decl_Type2".
148 unification hint 0 ≔ A,a,a'
149 (*-----------------------------------------------------------------*) ⊢
150 eq_rel ? (eq0 A) a a' ≡ eq_rel1 ? (eq1 (setoid1_of_setoid A)) a a'.
152 nlemma intersect_is_ext: ∀A. 𝛀^A → 𝛀^A → 𝛀^A.
153 #A; #S; #S'; @ (S ∩ S');
154 #a; #a'; #Ha; @; *; #H1; #H2; @
155 [##1,2: napply (. Ha^-1‡#); nassumption;
156 ##|##3,4: napply (. Ha‡#); nassumption]
159 alias symbol "hint_decl" = "hint_decl_Type1".
161 A : setoid, B,C : ext_powerclass A;
162 R ≟ (mk_ext_powerclass ? (B ∩ C) (ext_prop ? (intersect_is_ext ? B C)))
164 (* ------------------------------------------*) ⊢
165 ext_carr A R ≡ intersect ? (ext_carr ? B) (ext_carr ? C).
167 nlemma intersect_is_morph:
168 ∀A. unary_morphism1 (powerclass_setoid A) (unary_morphism1_setoid1 (powerclass_setoid A) (powerclass_setoid A)).
169 #A; napply (mk_binary_morphism1 … (λS,S'. S ∩ S'));
170 #a; #a'; #b; #b'; *; #Ha1; #Ha2; *; #Hb1; #Hb2; @; #x; nnormalize; *;/3/.
173 alias symbol "hint_decl" = "hint_decl_Type1".
175 A : Type[0], B,C : Ω^A;
176 R ≟ (mk_unary_morphism1 …
177 (λS. mk_unary_morphism1 … (λS'.S ∩ S') (prop11 … (intersect_is_morph A S)))
178 (prop11 … (intersect_is_morph A)))
180 R B C ≡ intersect ? B C.
182 interpretation "prop21 ext" 'prop2 l r =
183 (prop11 (ext_powerclass_setoid ?)
184 (unary_morphism1_setoid1 (ext_powerclass_setoid ?) ?) ? ?? l ?? r).
186 nlemma intersect_is_ext_morph:
187 ∀A. unary_morphism1 (ext_powerclass_setoid A)
188 (unary_morphism1_setoid1 (ext_powerclass_setoid A) (ext_powerclass_setoid A)).
189 #A; napply (mk_binary_morphism1 … (intersect_is_ext …));
190 #a; #a'; #b; #b'; #Ha; #Hb; napply (prop11 … (intersect_is_morph A)); nassumption.
194 AA : setoid, B,C : 𝛀^AA;
196 R ≟ (mk_unary_morphism1 …
197 (λS:ext_powerclass_setoid AA.
198 mk_unary_morphism1 ??
199 (λS':ext_powerclass_setoid AA.
200 mk_ext_powerclass AA (S∩S') (ext_prop AA (intersect_is_ext ? S S')))
201 (prop11 … (intersect_is_ext_morph AA S)))
202 (prop11 … (intersect_is_ext_morph AA))) ,
205 (* ------------------------------------------------------*) ⊢
206 ext_carr AA (R B C) ≡ intersect A BB CC.
209 alias symbol "hint_decl" = "hint_decl_Type2".
211 A : setoid, B,C : 𝛀^A ;
214 C1 ≟ (carr1 (powerclass_setoid (carr A))),
215 C2 ≟ (carr1 (ext_powerclass_setoid A))
217 eq_rel1 C1 (eq1 (powerclass_setoid (carr A))) BB CC ≡
218 eq_rel1 C2 (eq1 (ext_powerclass_setoid A)) B C.
221 A, B : CPROP ⊢ iff A B ≡ eq_rel1 ? (eq1 CPROP) A B.
223 nlemma test: ∀U.∀A,B:𝛀^U. A ∩ B = A →
224 ∀x,y. x=y → x ∈ A → y ∈ A ∩ B.
225 #U; #A; #B; #H; #x; #y; #K; #K2;
226 alias symbol "prop2" = "prop21 mem".
227 alias symbol "invert" = "setoid1 symmetry".
233 nlemma intersect_ok: ∀A. binary_morphism1 (ext_powerclass_setoid A) (ext_powerclass_setoid A) (ext_powerclass_setoid A).
238 nwhd in ⊢ (? ? ? % %); @; *; #H1; #H2; @
239 [##1,2: napply (. Ha^-1‡#); nassumption;
240 ##|##3,4: napply (. Ha‡#); nassumption]##]
241 ##| #a; #a'; #b; #b'; #Ha; #Hb; nwhd; @; #x; nwhd in ⊢ (% → %); #H
242 [ alias symbol "invert" = "setoid1 symmetry".
243 alias symbol "refl" = "refl".
244 alias symbol "prop2" = "prop21".
245 napply (. ((#‡Ha^-1)‡(#‡Hb^-1))); nassumption
246 | napply (. ((#‡Ha)‡(#‡Hb))); nassumption ]##]
249 (* unfold if intersect, exposing fun21 *)
250 alias symbol "hint_decl" = "hint_decl_Type1".
252 A : setoid, B,C : ext_powerclass A ⊢
254 (mk_binary_morphism1 …
255 (λS,S':qpowerclass_setoid A.mk_qpowerclass ? (S ∩ S') (mem_ok' ? (intersect_ok ? S S')))
256 (prop21 … (intersect_ok A)))
259 ≡ intersect ? (pc ? B) (pc ? C).
261 nlemma test: ∀A:setoid. ∀U,V:qpowerclass A. ∀x,x':setoid1_of_setoid A. x=x' → x ∈ U ∩ V → x' ∈ U ∩ V.
262 #A; #U; #V; #x; #x'; #H; #p; napply (. (H^-1‡#)); nassumption.
266 ndefinition image: ∀A,B. (carr A → carr B) → Ω^A → Ω^B ≝
267 λA,B:setoid.λf:carr A → carr B.λSa:Ω^A.
268 {y | ∃x. x ∈ Sa ∧ eq_rel (carr B) (eq0 B) (f x) y}.
270 ndefinition counter_image: ∀A,B. (carr A → carr B) → Ω^B → Ω^A ≝
271 λA,B,f,Sb. {x | ∃y. y ∈ Sb ∧ f x = y}.
273 (******************* compatible equivalence relations **********************)
275 nrecord compatible_equivalence_relation (A: setoid) : Type[1] ≝
276 { rel:> equivalence_relation A;
277 compatibility: ∀x,x':A. x=x' → rel x x'
280 ndefinition quotient: ∀A. compatible_equivalence_relation A → setoid.
284 (******************* first omomorphism theorem for sets **********************)
286 ndefinition eqrel_of_morphism:
287 ∀A,B. unary_morphism A B → compatible_equivalence_relation A.
289 [ @ [ napply (λx,y. f x = f y) ] /2/;
290 ##| #x; #x'; #H; nwhd; alias symbol "prop1" = "prop1".
291 napply (.= (†H)); // ]
294 ndefinition canonical_proj: ∀A,R. unary_morphism A (quotient A R).
296 [ napply (λx.x) | #a; #a'; #H; napply (compatibility … R … H) ]
299 ndefinition quotiented_mor:
300 ∀A,B.∀f:unary_morphism A B.
301 unary_morphism (quotient … (eqrel_of_morphism … f)) B.
302 #A; #B; #f; @ [ napply f ] //.
305 nlemma first_omomorphism_theorem_functions1:
306 ∀A,B.∀f: unary_morphism A B.
307 ∀x. f x = quotiented_mor … (canonical_proj … (eqrel_of_morphism … f) x).
310 alias symbol "eq" = "setoid eq".
311 ndefinition surjective ≝
312 λA,B.λS: ext_powerclass A.λT: ext_powerclass B.λf:unary_morphism A B.
313 ∀y. y ∈ T → ∃x. x ∈ S ∧ f x = y.
315 ndefinition injective ≝
316 λA,B.λS: ext_powerclass A.λf:unary_morphism A B.
317 ∀x,x'. x ∈ S → x' ∈ S → f x = f x' → x = x'.
319 nlemma first_omomorphism_theorem_functions2:
320 ∀A,B.∀f: unary_morphism A B.
321 surjective … (Full_set ?) (Full_set ?) (canonical_proj ? (eqrel_of_morphism … f)).
324 nlemma first_omomorphism_theorem_functions3:
325 ∀A,B.∀f: unary_morphism A B.
326 injective … (Full_set ?) (quotiented_mor … f).
327 #A; #B; #f; nwhd; #x; #x'; #Hx; #Hx'; #K; nassumption.
330 nrecord isomorphism (A, B : setoid) (S: ext_powerclass A) (T: ext_powerclass B) : Type[0] ≝
331 { iso_f:> unary_morphism A B;
332 f_closed: ∀x. x ∈ S → iso_f x ∈ T;
333 f_sur: surjective … S T iso_f;
334 f_inj: injective … S iso_f
337 nlemma subseteq_intersection_l: ∀A.∀U,V,W:Ω^A.U ⊆ W ∨ V ⊆ W → U ∩ V ⊆ W.
338 #A; #U; #V; #W; *; #H; #x; *; /2/.
341 nlemma subseteq_union_l: ∀A.∀U,V,W:Ω^A.U ⊆ W → V ⊆ W → U ∪ V ⊆ W.
342 #A; #U; #V; #W; #H; #H1; #x; *; /2/.
345 nlemma subseteq_intersection_r: ∀A.∀U,V,W:Ω^A.W ⊆ U → W ⊆ V → W ⊆ U ∩ V.
349 nrecord isomorphism (A, B : setoid) (S: qpowerclass A) (T: qpowerclass B) : CProp[0] ≝
350 { iso_f:> unary_morphism A B;
351 f_closed: ∀x. x ∈ pc A S → fun1 ?? iso_f x ∈ pc B T}.
358 λxxx:isomorphism A B S T.
360 return λxxx:isomorphism A B S T.
362 ∀x_72: mem (carr A) (pc A S) x.
363 mem (carr B) (pc B T) (fun1 A B ((λ_.?) A B S T xxx) x)
364 with [ mk_isomorphism _ yyy ⇒ yyy ] ).