ndefinition union ≝ λA.λU,V:Ω^A.{ x | x ∈ U ∨ x ∈ V }.
interpretation "union" 'union U V = (union ? U V).
+ndefinition substract ≝ λA.λU,V:Ω^A.{ x | x ∈ U ∧ ¬ x ∈ V }.
+interpretation "substract" 'minus U V = (substract ? U V).
+
+
ndefinition big_union ≝ λA,B.λT:Ω^A.λf:A → Ω^B.{ x | ∃i. i ∈ T ∧ x ∈ f i }.
ndefinition big_intersection ≝ λA,B.λT:Ω^A.λf:A → Ω^B.{ x | ∀i. i ∈ T → x ∈ f i }.
include "sets/setoids1.ma".
+ndefinition singleton ≝ λA:setoid.λa:A.{ x | a = x }.
+interpretation "singl" 'singl a = (singleton ? a).
+
(* this has to be declared here, so that it is combined with carr *)
ncoercion full_set : ∀A:Type[0]. Ω^A ≝ full_set on A: Type[0] to (Ω^?).
#a; #a'; #b; #b'; *; #H1; #H2; *; /5/ by mk_iff, sym1, subseteq_trans;
nqed.
-alias symbol "hint_decl" (instance 1) = "hint_decl_Type2".
-unification hint 0 ≔ A,x,y
-(*-----------------------------------------------*) ⊢
- eq_rel ? (eq0 A) x y ≡ eq_rel1 ? (eq1 (setoid1_of_setoid A)) x y.
-
-(* XXX capire come mai questa hint non funziona se porto su (setoid1_of_setoid A) *)
-
+(* hints for ∩ *)
nlemma intersect_is_ext: ∀A. 𝛀^A → 𝛀^A → 𝛀^A.
#S A B; @ (A ∩ B); #x y Exy; @; *; #H1 H2; @;
##[##1,2: napply (. Exy^-1‡#); nassumption;
(* ------------------------------------------------------*) ⊢
ext_carr AA (R B C) ≡ intersect A BB CC.
+
+(* hints for ∩ *)
nlemma union_is_morph : ∀A. Ω^A ⇒_1 (Ω^A ⇒_1 Ω^A).
#X; napply (mk_binary_morphism1 … (λA,B.A ∪ B));
#A1 A2 B1 B2 EA EB; napply ext_set; #x;
(*------------------------------------------------------*) ⊢
ext_carr AA (R B C) ≡ union A BB CC.
+
+(* hints for - *)
+nlemma substract_is_morph : ∀A. Ω^A ⇒_1 (Ω^A ⇒_1 Ω^A).
+#X; napply (mk_binary_morphism1 … (λA,B.A - B));
+#A1 A2 B1 B2 EA EB; napply ext_set; #x;
+nchange in match (x ∈ (A1 - B1)) with (?∧?);
+napply (.= (set_ext ??? EA x)‡#); @; *; #H H1; @; //; #H2; napply H1;
+##[ napply (. (set_ext ??? EB x)); ##| napply (. (set_ext ??? EB^-1 x)); ##] //;
+nqed.
+
+nlemma substract_is_ext: ∀A. 𝛀^A → 𝛀^A → 𝛀^A.
+ #S A B; @ (A - B); #x y Exy; @; *; #H1 H2; @; ##[##2,4: #H3; napply H2]
+##[##1,4: napply (. Exy╪_1#); // ##|##2,3: napply (. Exy^-1╪_1#); //]
+nqed.
+
+alias symbol "hint_decl" = "hint_decl_Type1".
+unification hint 0 ≔
+ A : setoid, B,C : 𝛀^A;
+ R ≟ (mk_ext_powerclass ? (B - C) (ext_prop ? (substract_is_ext ? B C)))
+(*-------------------------------------------------------------------------*) ⊢
+ ext_carr A R ≡ substract ? (ext_carr ? B) (ext_carr ? C).
+
+unification hint 0 ≔ S:Type[0], A,B:Ω^S;
+ MM ≟ mk_unary_morphism1 ??
+ (λA.mk_unary_morphism1 ?? (λB.A - B) (prop11 ?? (substract_is_morph S A)))
+ (prop11 ?? (substract_is_morph S))
+(*--------------------------------------------------------------------------*) ⊢
+ fun11 ?? (fun11 ?? MM A) B ≡ A - B.
+
+nlemma substract_is_ext_morph:∀A.𝛀^A ⇒_1 𝛀^A ⇒_1 𝛀^A.
+#A; napply (mk_binary_morphism1 … (substract_is_ext …));
+#x1 x2 y1 y2 Ex Ey; napply (prop11 … (substract_is_morph A)); nassumption.
+nqed.
+
+unification hint 1 ≔
+ AA : setoid, B,C : 𝛀^AA;
+ A ≟ carr AA,
+ R ≟ (mk_unary_morphism1 ??
+ (λS:𝛀^AA.
+ mk_unary_morphism1 ??
+ (λS':𝛀^AA.
+ mk_ext_powerclass AA (S - S') (ext_prop AA (substract_is_ext ? S S')))
+ (prop11 ?? (substract_is_ext_morph AA S)))
+ (prop11 ?? (substract_is_ext_morph AA))) ,
+ BB ≟ (ext_carr ? B),
+ CC ≟ (ext_carr ? C)
+(*------------------------------------------------------*) ⊢
+ ext_carr AA (R B C) ≡ substract A BB CC.
+
+(* hints for {x} *)
+nlemma single_is_morph : ∀A:setoid. (setoid1_of_setoid A) ⇒_1 Ω^A.
+#X; @; ##[ napply (λx.{(x)}); ##]
+#a b E; napply ext_set; #x; @; #H; /3/; nqed.
+
+nlemma single_is_ext: ∀A:setoid. A → 𝛀^A.
+#X a; @; ##[ napply ({(a)}); ##] #x y E; @; #H; /3/; nqed.
+
+alias symbol "hint_decl" = "hint_decl_Type1".
+unification hint 0 ≔ A : setoid, a:A;
+ R ≟ (mk_ext_powerclass ? {(a)} (ext_prop ? (single_is_ext ? a)))
+(*-------------------------------------------------------------------------*) ⊢
+ ext_carr A R ≡ singleton A a.
+
+unification hint 0 ≔ A:setoid, a:A;
+ MM ≟ mk_unary_morphism1 ??
+ (λa:setoid1_of_setoid A.{(a)}) (prop11 ?? (single_is_morph A))
+(*--------------------------------------------------------------------------*) ⊢
+ fun11 ?? MM a ≡ {(a)}.
+
+nlemma single_is_ext_morph:∀A:setoid.(setoid1_of_setoid A) ⇒_1 𝛀^A.
+#A; @; ##[ #a; napply (single_is_ext ? a); ##] #a b E; @; #x; /3/; nqed.
+
+unification hint 1 ≔
+ AA : setoid, a: AA;
+ R ≟ mk_unary_morphism1 ??
+ (λa:setoid1_of_setoid AA.
+ mk_ext_powerclass AA {(a)} (ext_prop ? (single_is_ext AA a)))
+ (prop11 ?? (single_is_ext_morph AA))
+(*------------------------------------------------------*) ⊢
+ ext_carr AA (R a) ≡ singleton AA a.
+
+
+
+
+
+
(*
alias symbol "hint_decl" = "hint_decl_Type2".
unification hint 0 ≔