Improved notatio

FiniteSets/_CoqProject

@@ -1,5 +1,6 @@
 -R . "" COQC = hoqc COQDEP = hoqdep
 -R ../prelude ""
+notation.v
 lattice.v
 disjunction.v
 representations/bad.v

FiniteSets/disjunction.v

@@ -1,6 +1,6 @@
 (* Logical disjunction in HoTT (see ch. 3 of the book) *)
 Require Import HoTT.
-Require Import lattice.
+Require Import lattice notation.
 
 Instance lor : maximum hProp := fun X Y => BuildhProp (Trunc (-1) (sum X Y)).
 

FiniteSets/fsets/isomorphism.v

@@ -12,25 +12,35 @@ Section Iso.
   Proof.
     hrecursion.
     - apply E.
-    - intros a x. apply (U (L a) x).
+    - intros a x.
+      apply ({|a|} ∪ x).
     - intros. cbn.  
       etransitivity. apply assoc.
-      apply (ap (fun y => U y x)).
+      apply (ap (∪ x)).
       apply idem.
     - intros. cbn.
       etransitivity. apply assoc.
-      etransitivity. refine (ap (fun y => U y x) _ ).
+      etransitivity. refine (ap (∪ x) _ ).
       apply FSet.comm.
       symmetry. 
       apply assoc.
   Defined.
 
-  Definition FSet_to_FSetC: FSet A -> FSetC A :=
+  Definition FSet_to_FSetC: FSet A -> FSetC A.
-    FSet_rec A (FSetC A) (FSetC.trunc A) Nil singleton append append_assoc 
+  Proof.
-             append_comm append_nl append_nr singleton_idem.
+    hrecursion.
+    - apply ∅.
+    - intro a. apply {|a|}.
+    - intros X Y. apply (X ∪ Y).
+    - apply append_assoc.
+    - apply append_comm.
+    - apply append_nl.
+    - apply append_nr.
+    - apply singleton_idem.
+  Defined.
 
   Lemma append_union: forall (x y: FSetC A), 
-      FSetC_to_FSet (append x y) = U (FSetC_to_FSet x) (FSetC_to_FSet y).
+      FSetC_to_FSet (x ∪ y) = (FSetC_to_FSet x) ∪ (FSetC_to_FSet y).
   Proof.
     intros x. 
     hrecursion x; try (intros; apply path_forall; intro; apply set_path2).

FiniteSets/fsets/monad.v

@@ -8,7 +8,7 @@ Proof.
   hrecursion.
   - exact ∅.
   - intro a. exact {| f a |}.
-  - exact U.
+  - intros X Y. apply (X ∪ Y).
   - apply assoc.
   - apply comm.
   - apply nl.
@@ -39,7 +39,7 @@ Proof.
 hrecursion.
 - exact ∅.
 - exact idmap.
-- exact U.
+- intros X Y. apply (X ∪ Y).
 - apply assoc.
 - apply comm.
 - apply nl.

FiniteSets/fsets/operations.v

@@ -23,32 +23,6 @@ Section operations.
     - intros ; apply lor_idem.
   Defined.
 
-  Definition subset : FSet A -> FSet A -> hProp.
-  Proof.
-    intros X Y.
-    hrecursion X.
-    - exists Unit.
-      exact _.
-    - intros a.
-      apply (isIn a Y).
-    - intros X1 X2.
-      exists (prod X1 X2).
-      exact _.
-    - intros.
-      apply path_trunctype ; apply equiv_prod_assoc.
-    - intros.
-      apply path_trunctype ; apply equiv_prod_symm.
-    - intros.
-      apply path_trunctype ; apply prod_unit_l.
-    - intros.
-      apply path_trunctype ; apply prod_unit_r.
-    - intros a'.
-      apply path_iff_hprop ; cbn.
-      * intros [p1 p2]. apply p1.
-      * intros p.
-        split ; apply p.
-  Defined.
-
   Definition comprehension : 
     (A -> Bool) -> FSet A -> FSet A.
   Proof.
@@ -57,7 +31,7 @@ Section operations.
     - apply ∅.
     - intro a.
       refine (if (P a) then {|a|} else ∅).
-    - apply U.
+    - apply (∪).
     - apply assoc.
     - apply comm.
     - apply nl.
@@ -82,7 +56,7 @@ Section operations.
     - apply ∅.
     - intro b.
       apply {|(a, b)|}.
-    - apply U.
+    - apply (∪).
     - intros X Y Z ; apply assoc.
     - intros X Y ; apply comm.
     - intros ; apply nl.
@@ -97,7 +71,7 @@ Section operations.
     - apply ∅.
     - intro a.
       apply (single_product a Y).
-    - apply U.
+    - apply (∪).
     - intros ; apply assoc.
     - intros ; apply comm.
     - intros ; apply nl.
@@ -107,5 +81,48 @@ Section operations.
   
 End operations.
 
-Infix "∈" := isIn (at level 9, right associativity).
+Section instances_operations.
+  Global Instance fset_comprehension : hasComprehension FSet.
+  Proof.
+    intros A ϕ X.
+    apply (comprehension ϕ X).
+  Defined.
+
+  Context `{Univalence}.
+
+  Global Instance fset_member : hasMembership FSet.
+  Proof.
+    intros A a X.
+    apply (isIn a X).
+  Defined.
+
+  Context {A : Type}.
+  
+  Definition subset : FSet A -> FSet A -> hProp.
+  Proof.
+    intros X Y.
+    hrecursion X.
+    - exists Unit.
+      exact _.
+    - intros a.
+      apply (a ∈ Y).
+    - intros X1 X2.
+      exists (prod X1 X2).
+      exact _.
+    - intros.
+      apply path_trunctype ; apply equiv_prod_assoc.
+    - intros.
+      apply path_trunctype ; apply equiv_prod_symm.
+    - intros.
+      apply path_trunctype ; apply prod_unit_l.
+    - intros.
+      apply path_trunctype ; apply prod_unit_r.
+    - intros a'.
+      apply path_iff_hprop ; cbn.
+      * intros [p1 p2]. apply p1.
+      * intros p.
+        split ; apply p.
+  Defined.
+End instances_operations.
+
 Infix  "⊆" := subset (at level 10, right associativity).

FiniteSets/fsets/operations_cons_repr.v

@@ -4,9 +4,9 @@ Require Import representations.cons_repr.
 
 Section operations.
 
-  Context {A : Type}.
+  Global Instance fsetc_union : hasUnion FSetC.
-
+  Proof.
-  Definition append  (x y: FSetC A) : FSetC A.
+    intros A x y.
     hinduction x.
     - apply y.
     - apply Cns.
@@ -14,6 +14,6 @@ Section operations.
     - apply comm.
   Defined.
 
-  Definition singleton (a:A) : FSetC A := a;;∅.
+  Global Instance fsetc_singleton : hasSingleton FSetC := fun A a => a;;∅.
 
 End operations.

FiniteSets/fsets/operations_decidable.v

@@ -33,7 +33,7 @@ Section decidable_A.
   Proof.
     hinduction ; try (intros ; apply path_ishprop).
     - intro ; apply _.
-    - intros ; apply _. 
+    - intros. apply _. 
     - intros ; apply _.
   Defined.
 

FiniteSets/fsets/properties.v

@@ -9,17 +9,23 @@ Section characterize_isIn.
   Context `{Univalence}.
 
   (** isIn properties *)
-  Definition empty_isIn (a: A) : a ∈ E -> Empty := idmap.
+  Definition empty_isIn (a: A) : a ∈ ∅ -> Empty := idmap.
   
   Definition singleton_isIn (a b: A) : a ∈ {|b|} -> Trunc (-1) (a = b) := idmap.
 
   Definition union_isIn (X Y : FSet A) (a : A)
     : a ∈ X ∪ Y = a ∈ X ∨ a ∈ Y := idpath.
 
-  Lemma comprehension_isIn (ϕ : A -> Bool) (a : A) : forall X : FSet A,
+  Lemma comprehension_union (ϕ : A -> Bool) : forall X Y : FSet A,
-      a ∈ (comprehension ϕ X) = if ϕ a then a ∈ X else False_hp.
+      {|X ∪ Y & ϕ|} = {|X & ϕ|} ∪ {|Y & ϕ|}.
   Proof.
-    hinduction ; try (intros ; apply set_path2) ; cbn.
+    reflexivity.
+  Defined.  
+
+  Lemma comprehension_isIn (ϕ : A -> Bool) (a : A) : forall X : FSet A,
+      a ∈ {|X & ϕ|} = if ϕ a then a ∈ X else False_hp.
+  Proof.
+    hinduction ; try (intros ; apply set_path2).
     - destruct (ϕ a) ; reflexivity.
     - intros b.
       assert (forall c d, ϕ a = c -> ϕ b = d ->
@@ -36,6 +42,8 @@ Section characterize_isIn.
       }
       apply (X (ϕ a) (ϕ b) idpath idpath).
     - intros X Y H1 H2.
+      rewrite comprehension_union.
+      rewrite union_isIn.
       rewrite H1, H2.
       destruct (ϕ a).
       * reflexivity.
@@ -44,11 +52,14 @@ Section characterize_isIn.
            destruct Z ; assumption.
         ** intros ; apply tr ; right ; assumption.
   Defined.
+End characterize_isIn.
 
-  Context {B : Type}.
+Section product_isIn.
+  Context {A B : Type}.
+  Context `{Univalence}.
   
   Lemma isIn_singleproduct (a : A) (b : B) (c : A) : forall (Y : FSet B),
-      isIn (a, b) (single_product c Y) = land (BuildhProp (Trunc (-1) (a = c))) (isIn b Y).
+      (a, b) ∈ (single_product c Y) = land (BuildhProp (Trunc (-1) (a = c))) (b ∈ Y).
   Proof.
     hinduction ; try (intros ; apply path_ishprop).
     - apply path_hprop ; symmetry ; apply prod_empty_r.
@@ -62,7 +73,7 @@ Section characterize_isIn.
         rewrite Z1, Z2.
         apply (tr idpath).
     - intros X1 X2 HX1 HX2.
-      apply path_iff_hprop.
+      apply path_iff_hprop ; rewrite ?union_isIn.
       * intros X.
         strip_truncations.
         destruct X as [H1 | H1] ; rewrite ?HX1, ?HX2 in H1 ; destruct H1 as [H1 H2].
@@ -84,15 +95,16 @@ Section characterize_isIn.
   Defined.
   
   Definition isIn_product (a : A) (b : B) (X : FSet A) (Y : FSet B) :
-    isIn (a,b) (product X Y) = land (isIn a X) (isIn b Y).
+    (a,b) ∈ (product X Y) = land (a ∈ X) (b ∈ Y).
   Proof.
     hinduction X ; try (intros ; apply path_ishprop).
     - apply path_hprop ; symmetry ; apply prod_empty_l.
     - intros.
       apply isIn_singleproduct.
     - intros X1 X2 HX1 HX2.
+      rewrite (union_isIn (product X1 Y)).
       rewrite HX1, HX2.
-      apply path_iff_hprop.
+      apply path_iff_hprop ; rewrite ?union_isIn.
       * intros X.
         strip_truncations.
         destruct X as [[H3 H4] | [H3 H4]] ; split ; try (apply H4).
@@ -104,7 +116,7 @@ Section characterize_isIn.
         ** left ; split ; assumption.
         ** right ; split ; assumption.
   Defined.
-End characterize_isIn.
+End product_isIn.
 
 Ltac simplify_isIn :=
   repeat (rewrite union_isIn
@@ -120,8 +132,17 @@ Section properties.
   Context {A : Type}.
   Context `{Univalence}.
 
-  Instance: bottom(FSet A) := ∅.
+  Instance: bottom(FSet A).
-  Instance: maximum(FSet A) := U.
+  Proof.
+    unfold bottom.
+    apply ∅.
+  Defined.
+
+  Instance: maximum(FSet A).
+  Proof.
+    intros x y.
+    apply (x ∪ y).
+  Defined.
 
   Global Instance joinsemilattice_fset : JoinSemiLattice (FSet A).
   Proof.
@@ -129,27 +150,33 @@ Section properties.
   Defined.  
 
   (** comprehension properties *)
-  Lemma comprehension_false Y : comprehension (fun (_ : A) => false) Y = ∅.
+  Lemma comprehension_false X : {|X & (fun (_ : A) => false)|} = ∅.
   Proof.
     toHProp.
   Defined.
 
   Lemma comprehension_subset : forall ϕ (X : FSet A),
-      (comprehension ϕ X) ∪ X = X.
+      {|X & ϕ|} ∪ X = X.
   Proof.
     toHProp.
     destruct (ϕ a) ; eauto with lattice_hints typeclass_instances.
   Defined.
 
-  Lemma comprehension_or : forall ϕ ψ (x: FSet A),
+  Lemma comprehension_or : forall ϕ ψ (X : FSet A),
-      comprehension (fun a => orb (ϕ a) (ψ a)) x
+      {|X & (fun a => orb (ϕ a) (ψ a))|}
-      = (comprehension ϕ x) ∪ (comprehension ψ x).
+      = {|X & ϕ|} ∪ {|X & ψ|}.
   Proof.
     toHProp.
     symmetry ; destruct (ϕ a) ; destruct (ψ a)
     ; eauto with lattice_hints typeclass_instances.
   Defined.
 
+  Lemma comprehension_all : forall (X : FSet A),
+      comprehension (fun a => true) X = X.
+  Proof.
+    toHProp.
+  Defined.
+  
   Lemma merely_choice : forall X : FSet A, hor (X = ∅) (hexists (fun a => a ∈ X)).
   Proof.
     hinduction; try (intros; apply equiv_hprop_allpath ; apply _).
@@ -161,7 +188,7 @@ Section properties.
       destruct TX as [XE | HX] ; destruct TY as [YE | HY] ; try(strip_truncations ; apply tr).
       * refine (tr (inl _)).
         rewrite XE, YE.
-        apply (union_idem E).
+        apply (union_idem ∅).
       * destruct HY as [a Ya].
         refine (inr (tr _)).
         exists a.

FiniteSets/fsets/properties_cons_repr.v

@@ -6,38 +6,30 @@ From fsets Require Import operations_cons_repr.
 Section properties.
   Context {A : Type}.
 
-  Lemma append_nl: 
+  Definition append_nl : forall (x: FSetC A), ∅ ∪ x = x
-    forall (x: FSetC A), append ∅ x = x. 
+    := fun _ => idpath. 
-  Proof.
-    intro. reflexivity.
-  Defined.
 
-  Lemma append_nr: 
+  Lemma append_nr : forall (x: FSetC A), x ∪ ∅ = x.
-    forall (x: FSetC A), append x ∅ = x.
   Proof.
     hinduction; try (intros; apply set_path2).
     -  reflexivity.
-    -  intros. apply (ap (fun y => a ;; y) X).
+    -  intros. apply (ap (fun y => a;;y) X).
   Defined.
   
   Lemma append_assoc {H: Funext}:  
-    forall (x y z: FSetC A), append x (append y z) = append (append x y) z.
+    forall (x y z: FSetC A), x ∪ (y ∪ z) = (x ∪ y) ∪ z.
   Proof.
-    intro x; hinduction x; try (intros; apply set_path2).
+    hinduction
+    ; try (intros ; apply path_forall ; intro
+           ; apply path_forall ; intro ;  apply set_path2).
     - reflexivity.
     - intros a x HR y z. 
       specialize (HR y z).
-      apply (ap (fun y => a ;; y) HR). 
+      apply (ap (fun y => a;;y) HR). 
-    - intros. apply path_forall. 
-      intro. apply path_forall. 
-      intro. apply set_path2.
-    - intros. apply path_forall.
-      intro. apply path_forall. 
-      intro. apply set_path2.
   Defined.
   
   Lemma append_singleton: forall (a: A) (x: FSetC A), 
-      a ;; x = append x (a ;; ∅).
+      a ;; x = x ∪ (a ;; ∅).
   Proof.
     intro a. hinduction; try (intros; apply set_path2).
     - reflexivity.
@@ -47,29 +39,26 @@ Section properties.
   Defined.
 
   Lemma append_comm {H: Funext}: 
-    forall (x1 x2: FSetC A), append x1 x2 = append x2 x1.
+    forall (x1 x2: FSetC A), x1 ∪ x2 = x2 ∪ x1.
   Proof.
-    intro x1. 
+    hinduction ;  try (intros ; apply path_forall ; intro ; apply set_path2).
-    hinduction x1;  try (intros; apply set_path2).
     - intros. symmetry. apply append_nr. 
     - intros a x1 HR x2.
       etransitivity.
       apply (ap (fun y => a;;y) (HR x2)).  
-      transitivity  (append (append x2 x1) (a;;∅)).
+      transitivity  ((x2 ∪ x1) ∪ (a;;∅)).
       + apply append_singleton. 
       + etransitivity.
     	* symmetry. apply append_assoc.
-    	* simple refine (ap (fun y => append x2 y) (append_singleton _ _)^).
+    	* simple refine (ap (x2 ∪) (append_singleton _ _)^).
-    - intros. apply path_forall.
-      intro. apply set_path2.
-    - intros. apply path_forall.
-      intro. apply set_path2.  
   Defined.
 
   Lemma singleton_idem: forall (a: A), 
-      append (singleton a) (singleton a) = singleton a.
+      {|a|} ∪ {|a|} = {|a|}.
   Proof.
-    unfold singleton. intro. cbn. apply dupl.
+    unfold singleton.
+    intro.
+    apply dupl.
   Defined.
 
 End properties.

FiniteSets/fsets/properties_decidable.v

@@ -71,10 +71,10 @@ Section operations_isIn.
   Defined.
 
   Lemma comprehension_isIn_b (Y : FSet A) (ϕ : A -> Bool) (a : A) :
-    isIn_b a (comprehension ϕ Y) = andb (isIn_b a Y) (ϕ a).
+    isIn_b a {|Y & ϕ|} = andb (isIn_b a Y) (ϕ a).
   Proof.
     unfold isIn_b, dec ; simpl.
-    destruct (isIn_decidable a (comprehension ϕ Y)) as [t | t]
+    destruct (isIn_decidable a {|Y & ϕ|}) as [t | t]
     ; destruct (isIn_decidable a Y) as [n | n] ; rewrite comprehension_isIn in t
     ; destruct (ϕ a) ; try reflexivity ; try contradiction.
   Defined.
@@ -105,9 +105,23 @@ Section SetLattice.
   Context {A_deceq : DecidablePaths A}.
   Context `{Univalence}.
 
-  Instance fset_max : maximum (FSet A) := U.
+  Instance fset_max : maximum (FSet A).
-  Instance fset_min : minimum (FSet A) := intersection.
+  Proof.
-  Instance fset_bot : bottom (FSet A) := ∅.
+    intros x y.
+    apply (x ∪ y).
+  Defined.
+      
+  Instance fset_min : minimum (FSet A).
+  Proof.
+    intros x y.
+    apply (intersection x y).
+  Defined.
+  
+  Instance fset_bot : bottom (FSet A).
+  Proof.
+    unfold bottom.
+    apply ∅.
+  Defined.
     
   Instance lattice_fset : Lattice (FSet A).
   Proof.
@@ -116,40 +130,6 @@ Section SetLattice.
   
 End SetLattice.
 
-(* Comprehension properties *)
-Section comprehension_properties.
-
-  Context {A : Type}.
-  Context {A_deceq : DecidablePaths A}.
-  Context `{Univalence}.
-
-  Lemma comprehension_or : forall ϕ ψ (x: FSet A),
-      comprehension (fun a => orb (ϕ a) (ψ a)) x
-      = U (comprehension ϕ x) (comprehension ψ x).
-  Proof.
-    toBool.
-  Defined.
-  
-  (** comprehension properties *)
-  Lemma comprehension_false Y : comprehension (fun (_ : A) => false) Y = ∅.
-  Proof.
-    toBool.
-  Defined.
-
-  Lemma comprehension_all : forall (X : FSet A),
-      comprehension (fun a => isIn_b a X) X = X.
-  Proof.
-    toBool.
-  Defined.
-  
-  Lemma comprehension_subset : forall ϕ (X : FSet A),
-      (comprehension ϕ X) ∪ X = X.
-  Proof.
-    toBool.
-  Defined.
-  
-End comprehension_properties.
-
 (* With extensionality we can prove decidable equality *)
 Section dec_eq.
   Context (A : Type) `{DecidablePaths A} `{Univalence}.

FiniteSets/implementations/interface.v

@@ -1,31 +1,6 @@
 Require Import HoTT.
 Require Import FSets.
 
-Section structure.
-  Variable (T : Type -> Type).
-  
-  Class hasMembership : Type :=
-    member : forall A : Type, A -> T A -> hProp.
-
-  Class hasEmpty : Type :=
-    empty : forall A, T A.
-
-  Class hasSingleton : Type :=
-    singleton : forall A, A -> T A.
-  
-  Class hasUnion : Type :=
-    union : forall A, T A -> T A -> T A.
-
-  Class hasComprehension : Type :=
-    filter : forall A, (A -> Bool) -> T A -> T A.
-End structure.
-
-Arguments member {_} {_} {_} _ _.
-Arguments empty {_} {_} {_}.
-Arguments singleton {_} {_} {_} _.
-Arguments union {_} {_} {_} _ _.
-Arguments filter {_} {_} {_} _ _.
-
 Section interface.
   Context `{Univalence}.
   Variable (T : Type -> Type)

FiniteSets/lattice.v

@@ -1,16 +1,15 @@
 (* Typeclass for lattices *)
 Require Import HoTT.
+Require Import notation.
 
 Section binary_operation.
   Variable A : Type.
   
-  Definition operation := A -> A -> A.
-
   Class maximum :=
-    max_L : operation.
+    max_L : operation A.
 
   Class minimum :=
-    min_L : operation.
+    min_L : operation A.
 
   Class bottom :=
     empty : A.
@@ -20,41 +19,6 @@ Arguments max_L {_} {_} _.
 Arguments min_L {_} {_} _.
 Arguments empty {_}.
 
-Section Defs.
-  Variable A : Type.
-  Variable f : A -> A -> A.
-
-  Class Commutative :=
-    commutative : forall x y, f x y = f y x.
-
-  Class Associative :=
-    associativity : forall x y z, f (f x y) z = f x (f y z).
-
-  Class Idempotent :=
-    idempotency : forall x, f x x = x.
-
-  Variable g : operation A.
-
-  Class Absorption :=
-    absorb : forall x y, f x (g x y) = x.
-
-  Variable n : A.
-
-  Class NeutralL :=
-    neutralityL : forall x, f n x = x.
-
-  Class NeutralR :=
-    neutralityR : forall x, f x n = x.
-
-End Defs.
-
-Arguments Commutative {_} _.
-Arguments Associative {_} _.
-Arguments Idempotent {_} _.
-Arguments NeutralL {_} _ _.
-Arguments NeutralR {_} _ _.
-Arguments Absorption {_} _ _.
-
 Section JoinSemiLattice.
   Variable A : Type.
   Context {max_L : maximum A} {empty_L : bottom A}.

FiniteSets/representations/bad.v

@@ -1,50 +1,45 @@
 (* This is a /bad/ definition of FSets, without the 0-truncation.
    Here we show that the resulting type is not an h-set. *)
 
-Require Import HoTT.
+Require Import HoTT HitTactics.
-Require Import HitTactics.
+Require Import notation.
+
 Module Export FSet.
   
   Section FSet.
+    Private Inductive FSet (A : Type): Type :=
+    | E : FSet A
+    | L : A -> FSet A
+    | U : FSet A -> FSet A -> FSet A.
+
+    Global Instance fset_empty : hasEmpty FSet := E.
+    Global Instance fset_singleton : hasSingleton FSet := L.
+    Global Instance fset_union : hasUnion FSet := U.
+
     Variable A : Type.
 
-    Private Inductive FSet : Type :=
+    Axiom assoc : forall (x y z : FSet A),
-    | E : FSet
-    | L : A -> FSet
-    | U : FSet -> FSet -> FSet.
-
-    Notation "{| x |}" :=  (L x).
-    Infix "∪" := U (at level 8, right associativity).
-    Notation "∅" := E.
-
-    Axiom assoc : forall (x y z : FSet ),
         x ∪ (y ∪ z) = (x ∪ y) ∪ z.
 
-    Axiom comm : forall (x y : FSet),
+    Axiom comm : forall (x y : FSet A),
         x ∪ y = y ∪ x.
 
-    Axiom nl : forall (x : FSet),
+    Axiom nl : forall (x : FSet A),
         ∅ ∪ x = x.
 
-    Axiom nr : forall (x : FSet),
+    Axiom nr : forall (x : FSet A),
         x ∪ ∅ = x.
 
     Axiom idem : forall (x : A),
-        {| x |} ∪ {|x|} = {|x|}.
+        {|x|} ∪ {|x|} = {|x|}.
 
   End FSet.
 
-  Arguments E {_}.
-  Arguments U {_} _ _.
-  Arguments L {_} _.
   Arguments assoc {_} _ _ _.
   Arguments comm {_} _ _.
   Arguments nl {_} _.
   Arguments nr {_} _.
   Arguments idem {_} _.
-  Notation "{| x |}" :=  (L x).
-  Infix "∪" := U (at level 8, right associativity).
-  Notation "∅" := E.
 
   Section FSet_induction.
     Variable A: Type.
@@ -74,12 +69,11 @@ Module Export FSet.
              {struct x}
       : P x
       := (match x return _ -> _ -> _ -> _ -> _ -> P x with
-          | ∅ => fun _ _ _ _ _ => eP
+          | E => fun _ _ _ _ _ => eP
-          | {|a|} => fun _ _ _ _ _ => lP a
+          | L a => fun _ _ _ _ _ => lP a
-          | y ∪ z => fun _ _ _ _ _ => uP y z (FSet_ind y) (FSet_ind z)
+          | U y z => fun _ _ _ _ _ => uP y z (FSet_ind y) (FSet_ind z)
           end) assocP commP nlP nrP idemP.
 
-
     Axiom FSet_ind_beta_assoc : forall (x y z : FSet A),
         apD FSet_ind (assoc x y z) =
         (assocP x y z (FSet_ind x) (FSet_ind y) (FSet_ind z)).
@@ -192,10 +186,6 @@ Module Export FSet.
 
 End FSet.
 
-Notation "{| x |}" :=  (L x).
-Infix "∪" := U (at level 8, right associativity).
-Notation "∅" := E.
-
 Section set_sphere.
   From HoTT.HIT Require Import Circle.
   Context `{Univalence}.
@@ -274,10 +264,10 @@ Section set_sphere.
     - simpl. reflexivity.
   Defined.
 
-  Lemma FSet_S_ap : (nl (@E A)) = (nr E) -> idpath = loop.
+  Lemma FSet_S_ap : (nl (E A)) = (nr ∅) -> idpath = loop.
   Proof.
     intros H1.
-    enough (ap FSet_to_S (nl E) = ap FSet_to_S (nr E)) as H'.
+    enough (ap FSet_to_S (nl ∅) = ap FSet_to_S (nr ∅)) as H'.
     - rewrite FSet_rec_beta_nl in H'. 
       rewrite FSet_rec_beta_nr in H'.
       simpl in H'. unfold S1op_nr in H'.

FiniteSets/representations/cons_repr.v

@@ -1,35 +1,35 @@
 (* Definition of Finite Sets as via cons lists *)
 Require Import HoTT HitTactics.
+Require Export notation.
 
 Module Export FSetC.
   
   Section FSetC.
+    Private Inductive FSetC (A : Type) : Type :=
+    | Nil : FSetC A
+    | Cns : A ->  FSetC A -> FSetC A.
+
+    Global Instance fset_empty : hasEmpty FSetC := Nil.
+
     Variable A : Type.
-
+    Arguments Cns {_} _ _.
-    Private Inductive FSetC : Type :=
-    | Nil : FSetC
-    | Cns : A ->  FSetC -> FSetC.
-
     Infix ";;" := Cns (at level 8, right associativity).
-    Notation "∅" := Nil.
     
-    Axiom dupl : forall (a: A) (x: FSetC),
+    Axiom dupl : forall (a : A) (x : FSetC A),
         a ;; a ;; x = a ;; x. 
 
-    Axiom comm : forall (a b: A) (x: FSetC),
+    Axiom comm : forall (a b : A) (x : FSetC A),
         a ;; b ;; x = b ;; a ;; x.
 
-    Axiom trunc : IsHSet FSetC.
+    Axiom trunc : IsHSet (FSetC A).
 
   End FSetC.
 
-  Arguments Nil {_}.
   Arguments Cns {_} _ _.
   Arguments dupl {_} _ _.
   Arguments comm {_} _ _ _.
 
   Infix ";;" := Cns (at level 8, right associativity).
-  Notation "∅" := Nil.
 
   Section FSetC_induction.
 
@@ -84,7 +84,6 @@ Module Export FSetC.
       - apply commP. 
     Defined.
 
-
     Definition FSetC_rec_beta_dupl : forall (a: A) (x : FSetC A),
         ap FSetC_rec (dupl a x) = duplP a (FSetC_rec x).
     Proof.
@@ -106,11 +105,12 @@ Module Export FSetC.
   End FSetC_recursion.
 
 
-  Instance FSetC_recursion A : HitRecursion (FSetC A) := {
+  Instance FSetC_recursion A : HitRecursion (FSetC A) :=
+    {
       indTy := _; recTy := _; 
-                                                          H_inductor := FSetC_ind A; H_recursor := FSetC_rec A }.
+      H_inductor := FSetC_ind A; H_recursor := FSetC_rec A
+    }.
 
 End FSetC.
 
 Infix ";;" := Cns (at level 8, right associativity).
-Notation "∅" := Nil.

FiniteSets/representations/definition.v

@@ -1,50 +1,44 @@
 (* Definitions of the Kuratowski-finite sets via a HIT *)
-Require Import HoTT.
+Require Import HoTT HitTactics.
-Require Import HitTactics.
+Require Export notation.
 
 Module Export FSet.
   Section FSet.
+    Private Inductive FSet (A : Type) : Type :=
+    | E : FSet A
+    | L : A -> FSet A
+    | U : FSet A -> FSet A -> FSet A.
+
+    Global Instance fset_empty : hasEmpty FSet := E.
+    Global Instance fset_singleton : hasSingleton FSet := L.
+    Global Instance fset_union : hasUnion FSet := U.
+
     Variable A : Type.
     
-    Private Inductive FSet : Type :=
+    Axiom assoc : forall (x y z : FSet A),
-    | E : FSet
-    | L : A -> FSet
-    | U : FSet -> FSet -> FSet.
-
-    Notation "{| x |}" :=  (L x).
-    Infix "∪" := U (at level 8, right associativity).
-    Notation "∅" := E.
-
-    Axiom assoc : forall (x y z : FSet ),
         x ∪ (y ∪ z) = (x ∪ y) ∪ z.
 
-    Axiom comm : forall (x y : FSet),
+    Axiom comm : forall (x y : FSet A),
         x ∪ y = y ∪ x.
 
-    Axiom nl : forall (x : FSet),
+    Axiom nl : forall (x : FSet A),
         ∅ ∪ x = x.
 
-    Axiom nr : forall (x : FSet),
+    Axiom nr : forall (x : FSet A),
         x ∪ ∅ = x.
 
     Axiom idem : forall (x : A),
-        {| x |} ∪ {|x|} = {|x|}.
+        {|x|} ∪ {|x|} = {|x|}.
 
-    Axiom trunc : IsHSet FSet.
+    Axiom trunc : IsHSet (FSet A).
 
   End FSet.
 
-  Arguments E {_}.
-  Arguments U {_} _ _.
-  Arguments L {_} _.
   Arguments assoc {_} _ _ _.
   Arguments comm {_} _ _.
   Arguments nl {_} _.
   Arguments nr {_} _.
   Arguments idem {_} _.  
-  Notation "{| x |}" :=  (L x).
-  Infix "∪" := U (at level 8, right associativity).
-  Notation "∅" := E.
 
   Section FSet_induction.
     Variable A: Type.
@@ -194,10 +188,6 @@ Module Export FSet.
 
 End FSet.
 
-Notation "{| x |}" :=  (L x).
-Infix "∪" := U (at level 8, right associativity).
-Notation "∅" := E.
-
 Lemma union_idem {A : Type} : forall x: FSet A, x ∪ x = x.
 Proof.
   hinduction ; try (intros ; apply set_path2).