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 \sup A.{ x | x ∈ U ∧ x ∈ V }.
32 interpretation "intersect" 'intersects U V = (intersect ? U V).
34 ndefinition union ≝ λA.λU,V:Ω \sup A.{ x | x ∈ U ∨ x ∈ V }.
35 interpretation "union" 'union U V = (union ? U V).
37 nlemma subseteq_refl: ∀A.∀S: Ω \sup A. S ⊆ S.
38 #A; #S; #x; #H; nassumption.
41 nlemma subseteq_trans: ∀A.∀S,T,U: Ω \sup A. S ⊆ T → T ⊆ U → S ⊆ U.
42 #A; #S; #T; #U; #H1; #H2; #x; #P; napply H2; napply H1; nassumption.
45 include "properties/relations1.ma".
47 ndefinition seteq: ∀A. equivalence_relation1 (Ω \sup A).
48 #A; napply mk_equivalence_relation1
49 [ napply (λS,S'. S ⊆ S' ∧ S' ⊆ S)
50 | #S; napply conj; napply subseteq_refl
51 | #S; #S'; *; #H1; #H2; napply conj; nassumption
52 | #S; #T; #U; *; #H1; #H2; *; #H3; #H4; napply conj; napply subseteq_trans;
53 ##[##2,5: nassumption |##1,4: ##skip |##*: nassumption]##]
56 include "sets/setoids1.ma".
58 ndefinition powerclass_setoid: Type[0] → setoid1.
64 (************ SETS OVER SETOIDS ********************)
66 include "logic/cprop.ma".
68 nrecord qpowerclass (A: setoid) : Type[1] ≝
70 mem_ok': ∀x,x':A. x=x' → (x ∈ pc) = (x' ∈ pc)
73 ndefinition qseteq: ∀A. equivalence_relation1 (qpowerclass A).
74 #A; napply mk_equivalence_relation1
75 [ napply (λS,S':qpowerclass A. eq_rel1 ? (eq1 (powerclass_setoid A)) S S')
76 | #S; napply (refl1 ? (seteq A))
77 | #S; #S'; napply (sym1 ? (seteq A))
78 | #S; #T; #U; napply (trans1 ? (seteq A))]
81 ndefinition qpowerclass_setoid: setoid → setoid1.
83 [ napply (qpowerclass A)
87 unification hint 0 (∀A. (λx,y.True) (carr1 (qpowerclass_setoid A)) (qpowerclass A)).
88 ncoercion qpowerclass_hint: ∀A: setoid. ∀S: qpowerclass_setoid A. Ω \sup A ≝ λA.λS.S
89 on _S: (carr1 (qpowerclass_setoid ?)) to (Ω \sup ?).
91 nlemma mem_ok: ∀A. binary_morphism1 (setoid1_of_setoid A) (qpowerclass_setoid A) CPROP.
92 #A; napply mk_binary_morphism1
93 [ napply (λx.λS: qpowerclass_setoid A. x ∈ S) (* CSC: ??? *)
94 | #a; #a'; #b; #b'; #Ha; #Hb; (* CSC: qui *; non funziona *)
95 nwhd; nwhd in ⊢ (? (? % ??) (? % ??)); napply mk_iff; #H
96 [ ncases Hb; #Hb1; #_; napply Hb1; napply (. (mem_ok' …))
97 [ nassumption | napply Ha^-1 | ##skip ]
98 ##| ncases Hb; #_; #Hb2; napply Hb2; napply (. (mem_ok' …))
99 [ nassumption | napply Ha | ##skip ]##]
102 unification hint 0 (∀A,x,S. (λx,y.True) (fun21 ??? (mem_ok A) x S) (mem A S x)).
104 nlemma subseteq_ok: ∀A. binary_morphism1 (qpowerclass_setoid A) (qpowerclass_setoid A) CPROP.
105 #A; napply mk_binary_morphism1
106 [ napply (λS,S': qpowerclass_setoid ?. S ⊆ S')
107 | #a; #a'; #b; #b'; *; #Ha1; #Ha2; *; #Hb1; #Hb2; napply mk_iff; #H
108 [ napply (subseteq_trans … a' a) (* anche qui, perche' serve a'? *)
109 [ nassumption | napply (subseteq_trans … a b); nassumption ]
110 ##| napply (subseteq_trans … a a') (* anche qui, perche' serve a'? *)
111 [ nassumption | napply (subseteq_trans … a' b'); nassumption ] ##]
114 nlemma intersect_ok: ∀A. binary_morphism1 (qpowerclass_setoid A) (qpowerclass_setoid A) (qpowerclass_setoid A).
115 #A; napply mk_binary_morphism1
116 [ #S; #S'; napply mk_qpowerclass
118 | #a; #a'; #Ha; nwhd in ⊢ (? ? ? % %); napply mk_iff; *; #H1; #H2; napply conj
119 [##1,2: napply (. (mem_ok' …)^-1) [##3,6: nassumption |##1,4: nassumption |##*: ##skip]
120 ##|##3,4: napply (. (mem_ok' …)) [##2,5: nassumption |##1,4: nassumption |##*: ##skip]##]##]
121 ##| #a; #a'; #b; #b'; #Ha; #Hb; nwhd; napply conj; #x; nwhd in ⊢ (% → %); #H
122 [ napply (. ((#‡Ha^-1)‡(#‡Hb^-1))); nassumption
123 | napply (. ((#‡Ha)‡(#‡Hb))); nassumption ]##]
126 unification hint 0 (∀A.∀U,V.(λx,y.True) (fun21 ??? (intersect_ok A) U V) (intersect A U V)).
128 nlemma test: ∀A:setoid. ∀U,V:qpowerclass A. ∀x,x':setoid1_of_setoid A. x=x' → x ∈ U ∩ V → x' ∈ U ∩ V.
129 #A; #U; #V; #x; #x'; #H; #p;
130 (* CSC: senza la change non funziona! *)
131 nchange with (x' ∈ (fun21 ??? (intersect_ok A) U V));
132 napply (. (H^-1‡#)); nassumption.
136 (* qui non funziona una cippa *)
137 ndefinition image: ∀A,B. (carr A → carr B) → Ω \sup A → Ω \sup B ≝
138 λA,B:setoid.λf:carr A → carr B.λSa:Ω \sup A.
139 {y | ∃x. x ∈ Sa ∧ eq_rel (carr B) (eq B) ? ?(*(f x) y*)}.
140 ##[##2: napply (f x); ##|##3: napply y]
141 #a; #a'; #H; nwhd; nnormalize; (* per togliere setoid1_of_setoid *) napply (mk_iff ????);
142 *; #x; #Hx; napply (ex_intro … x)
143 [ napply (. (#‡(#‡#)));
145 ndefinition counter_image: ∀A,B. (A → B) → Ω \sup B → Ω \sup A ≝
146 λA,B,f,Sb. {x | ∃y. y ∈ Sb ∧ f x = y}.