summaryrefslogtreecommitdiff
path: root/theories/FSets/FSetFacts.v
diff options
context:
space:
mode:
Diffstat (limited to 'theories/FSets/FSetFacts.v')
-rw-r--r--theories/FSets/FSetFacts.v48
1 files changed, 24 insertions, 24 deletions
diff --git a/theories/FSets/FSetFacts.v b/theories/FSets/FSetFacts.v
index d77d9c60..1e15d3a1 100644
--- a/theories/FSets/FSetFacts.v
+++ b/theories/FSets/FSetFacts.v
@@ -6,7 +6,7 @@
(* * GNU Lesser General Public License Version 2.1 *)
(***********************************************************************)
-(* $Id: FSetFacts.v 11282 2008-07-28 11:51:53Z msozeau $ *)
+(* $Id: FSetFacts.v 11720 2008-12-28 07:12:15Z letouzey $ *)
(** * Finite sets library *)
@@ -21,11 +21,9 @@ Require Export FSetInterface.
Set Implicit Arguments.
Unset Strict Implicit.
-(** First, a functor for Weak Sets. Since the signature [WS] includes
- an EqualityType and not a stronger DecidableType, this functor
- should take two arguments in order to compensate this. *)
+(** First, a functor for Weak Sets in functorial version. *)
-Module WFacts (Import E : DecidableType)(Import M : WSfun E).
+Module WFacts_fun (Import E : DecidableType)(Import M : WSfun E).
Notation eq_dec := E.eq_dec.
Definition eqb x y := if eq_dec x y then true else false.
@@ -293,12 +291,12 @@ End BoolSpec.
(** * [E.eq] and [Equal] are setoid equalities *)
-Definition E_ST : Setoid_Theory elt E.eq.
+Definition E_ST : Equivalence E.eq.
Proof.
constructor ; red; [apply E.eq_refl|apply E.eq_sym|apply E.eq_trans].
Qed.
-Definition Equal_ST : Setoid_Theory t Equal.
+Definition Equal_ST : Equivalence Equal.
Proof.
constructor ; red; [apply eq_refl | apply eq_sym | apply eq_trans].
Qed.
@@ -309,8 +307,6 @@ Add Relation elt E.eq
transitivity proved by E.eq_trans
as EltSetoid.
-Typeclasses unfold elt.
-
Add Relation t Equal
reflexivity proved by eq_refl
symmetry proved by eq_sym
@@ -418,18 +414,15 @@ Qed.
(* [Subset] is a setoid order *)
Lemma Subset_refl : forall s, s[<=]s.
-Proof. red; auto. Defined.
+Proof. red; auto. Qed.
Lemma Subset_trans : forall s s' s'', s[<=]s'->s'[<=]s''->s[<=]s''.
-Proof. unfold Subset; eauto. Defined.
+Proof. unfold Subset; eauto. Qed.
-Add Relation t Subset
+Add Relation t Subset
reflexivity proved by Subset_refl
transitivity proved by Subset_trans
as SubsetSetoid.
-(* NB: for the moment, it is important to use Defined and not Qed in
- the two previous lemmas, in order to allow conversion of
- SubsetSetoid coming from separate Facts modules. See bug #1738. *)
Instance In_s_m : Morphism (E.eq ==> Subset ++> impl) In | 1.
Proof.
@@ -480,28 +473,35 @@ Proof.
unfold Equal; intros; repeat rewrite filter_iff; auto; rewrite H0; tauto.
Qed.
+Lemma filter_ext : forall f f', compat_bool E.eq f -> (forall x, f x = f' x) ->
+ forall s s', s[=]s' -> filter f s [=] filter f' s'.
+Proof.
+intros f f' Hf Hff' s s' Hss' x. do 2 (rewrite filter_iff; auto).
+rewrite Hff', Hss'; intuition.
+red; intros; rewrite <- 2 Hff'; auto.
+Qed.
+
Lemma filter_subset : forall f, compat_bool E.eq f ->
forall s s', s[<=]s' -> filter f s [<=] filter f s'.
Proof.
unfold Subset; intros; rewrite filter_iff in *; intuition.
Qed.
-(* For [elements], [min_elt], [max_elt] and [choose], we would need setoid
+(* For [elements], [min_elt], [max_elt] and [choose], we would need setoid
structures on [list elt] and [option elt]. *)
(* Later:
Add Morphism cardinal ; cardinal_m.
*)
-End WFacts.
-
+End WFacts_fun.
-(** Now comes a special version dedicated to full sets. For this
- one, only one argument [(M:S)] is necessary. *)
+(** Now comes variants for self-contained weak sets and for full sets.
+ For these variants, only one argument is necessary. Thanks to
+ the subtyping [WS<=S], the [Facts] functor which is meant to be
+ used on modules [(M:S)] can simply be an alias of [WFacts]. *)
-Module Facts (Import M:S).
- Module D:=OT_as_DT M.E.
- Include WFacts D M.
+Module WFacts (M:WS) := WFacts_fun M.E M.
+Module Facts := WFacts.
-End Facts.