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Commit d27b81ff authored by Robbert Krebbers's avatar Robbert Krebbers
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Put option stuff in algebra/cmra and algebra/cofe.

parent a3d0a338
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_CoqProject
View file @ d27b81ff
......@@ -36,7 +36,6 @@ prelude/list.v
prelude/error.v
prelude/functions.v
prelude/hlist.v
algebra/option.v
algebra/cmra.v
algebra/cmra_big_op.v
algebra/cmra_tactics.v
......
algebra/cmra.v
View file @ d27b81ff
......@@ -441,6 +441,36 @@ Section cmra_monotone.
Proof. rewrite !cmra_valid_validN; eauto using validN_preserving. Qed.
End cmra_monotone.
(** Functors *)
Structure rFunctor := RFunctor {
rFunctor_car : cofeT → cofeT -> cmraT;
rFunctor_map {A1 A2 B1 B2} :
((A2 -n> A1) * (B1 -n> B2)) → rFunctor_car A1 B1 -n> rFunctor_car A2 B2;
rFunctor_ne A1 A2 B1 B2 n :
Proper (dist n ==> dist n) (@rFunctor_map A1 A2 B1 B2);
rFunctor_id {A B} (x : rFunctor_car A B) : rFunctor_map (cid,cid) x ≡ x;
rFunctor_compose {A1 A2 A3 B1 B2 B3}
(f : A2 -n> A1) (g : A3 -n> A2) (f' : B1 -n> B2) (g' : B2 -n> B3) x :
rFunctor_map (f◎g, g'◎f') x ≡ rFunctor_map (g,g') (rFunctor_map (f,f') x);
rFunctor_mono {A1 A2 B1 B2} (fg : (A2 -n> A1) * (B1 -n> B2)) :
CMRAMonotone (rFunctor_map fg)
}.
Existing Instances rFunctor_ne rFunctor_mono.
Instance: Params (@rFunctor_map) 5.
Class rFunctorContractive (F : rFunctor) :=
rFunctor_contractive A1 A2 B1 B2 :> Contractive (@rFunctor_map F A1 A2 B1 B2).
Definition rFunctor_diag (F: rFunctor) (A: cofeT) : cmraT := rFunctor_car F A A.
Coercion rFunctor_diag : rFunctor >-> Funclass.
Program Definition constRF (B : cmraT) : rFunctor :=
{| rFunctor_car A1 A2 := B; rFunctor_map A1 A2 B1 B2 f := cid |}.
Solve Obligations with done.
Instance constRF_contractive B : rFunctorContractive (constRF B).
Proof. rewrite /rFunctorContractive; apply _. Qed.
(** * Transporting a CMRA equality *)
Definition cmra_transport {A B : cmraT} (H : A = B) (x : A) : B :=
eq_rect A id x _ H.
......@@ -624,37 +654,6 @@ Proof.
- intros x y; rewrite !prod_included=> -[??] /=.
by split; apply included_preserving.
Qed.
(** Functors *)
Structure rFunctor := RFunctor {
rFunctor_car : cofeT → cofeT -> cmraT;
rFunctor_map {A1 A2 B1 B2} :
((A2 -n> A1) * (B1 -n> B2)) → rFunctor_car A1 B1 -n> rFunctor_car A2 B2;
rFunctor_ne A1 A2 B1 B2 n :
Proper (dist n ==> dist n) (@rFunctor_map A1 A2 B1 B2);
rFunctor_id {A B} (x : rFunctor_car A B) : rFunctor_map (cid,cid) x ≡ x;
rFunctor_compose {A1 A2 A3 B1 B2 B3}
(f : A2 -n> A1) (g : A3 -n> A2) (f' : B1 -n> B2) (g' : B2 -n> B3) x :
rFunctor_map (f◎g, g'◎f') x ≡ rFunctor_map (g,g') (rFunctor_map (f,f') x);
rFunctor_mono {A1 A2 B1 B2} (fg : (A2 -n> A1) * (B1 -n> B2)) :
CMRAMonotone (rFunctor_map fg)
}.
Existing Instances rFunctor_ne rFunctor_mono.
Instance: Params (@rFunctor_map) 5.
Class rFunctorContractive (F : rFunctor) :=
rFunctor_contractive A1 A2 B1 B2 :> Contractive (@rFunctor_map F A1 A2 B1 B2).
Definition rFunctor_diag (F: rFunctor) (A: cofeT) : cmraT := rFunctor_car F A A.
Coercion rFunctor_diag : rFunctor >-> Funclass.
Program Definition constRF (B : cmraT) : rFunctor :=
{| rFunctor_car A1 A2 := B; rFunctor_map A1 A2 B1 B2 f := cid |}.
Solve Obligations with done.
Instance constRF_contractive B : rFunctorContractive (constRF B).
Proof. rewrite /rFunctorContractive; apply _. Qed.
Program Definition prodRF (F1 F2 : rFunctor) : rFunctor := {|
rFunctor_car A B := prodR (rFunctor_car F1 A B) (rFunctor_car F2 A B);
rFunctor_map A1 A2 B1 B2 fg :=
......@@ -676,3 +675,137 @@ Proof.
intros ?? A1 A2 B1 B2 n ???;
by apply prodC_map_ne; apply rFunctor_contractive.
Qed.
(** ** CMRA for the option type *)
Section option.
Context {A : cmraT}.
Instance option_valid : Valid (option A) := λ mx,
match mx with Some x => ✓ x | None => True end.
Instance option_validN : ValidN (option A) := λ n mx,
match mx with Some x => ✓{n} x | None => True end.
Global Instance option_empty : Empty (option A) := None.
Instance option_core : Core (option A) := fmap core.
Instance option_op : Op (option A) := union_with (λ x y, Some (x ⋅ y)).
Definition Some_valid a : ✓ Some a ↔ ✓ a := reflexivity _.
Definition Some_op a b : Some (a ⋅ b) = Some a ⋅ Some b := eq_refl.
Lemma option_included (mx my : option A) :
mx ≼ my ↔ mx = None ∨ ∃ x y, mx = Some x ∧ my = Some y ∧ x ≼ y.
Proof.
split.
- intros [mz Hmz].
destruct mx as [x|]; [right|by left].
destruct my as [y|]; [exists x, y|destruct mz; inversion_clear Hmz].
destruct mz as [z|]; inversion_clear Hmz; split_and?; auto;
setoid_subst; eauto using cmra_included_l.
- intros [->|(x&y&->&->&z&Hz)]; try (by exists my; destruct my; constructor).
by exists (Some z); constructor.
Qed.
Definition option_cmra_mixin : CMRAMixin (option A).
Proof.
split.
- by intros n [x|]; destruct 1; constructor; cofe_subst.
- by destruct 1; constructor; cofe_subst.
- by destruct 1; rewrite /validN /option_validN //=; cofe_subst.
- intros [x|]; [apply cmra_valid_validN|done].
- intros n [x|]; unfold validN, option_validN; eauto using cmra_validN_S.
- intros [x|] [y|] [z|]; constructor; rewrite ?assoc; auto.
- intros [x|] [y|]; constructor; rewrite 1?comm; auto.
- by intros [x|]; constructor; rewrite cmra_core_l.
- by intros [x|]; constructor; rewrite cmra_core_idemp.
- intros mx my; rewrite !option_included ;intros [->|(x&y&->&->&?)]; auto.
right; exists (core x), (core y); eauto using cmra_core_preserving.
- intros n [x|] [y|]; rewrite /validN /option_validN /=;
eauto using cmra_validN_op_l.
- intros n mx my1 my2.
destruct mx as [x|], my1 as [y1|], my2 as [y2|]; intros Hx Hx';
try (by exfalso; inversion Hx'; auto).
+ destruct (cmra_extend n x y1 y2) as ([z1 z2]&?&?&?); auto.
{ by inversion_clear Hx'. }
by exists (Some z1, Some z2); repeat constructor.
+ by exists (Some x,None); inversion Hx'; repeat constructor.
+ by exists (None,Some x); inversion Hx'; repeat constructor.
+ exists (None,None); repeat constructor.
Qed.
Canonical Structure optionR :=
CMRAT (option A) option_cofe_mixin option_cmra_mixin.
Global Instance option_cmra_unit : CMRAUnit optionR.
Proof. split. done. by intros []. by inversion_clear 1. Qed.
Global Instance option_cmra_discrete : CMRADiscrete A → CMRADiscrete optionR.
Proof. split; [apply _|]. by intros [x|]; [apply (cmra_discrete_valid x)|]. Qed.
(** Misc *)
Global Instance Some_cmra_monotone : CMRAMonotone Some.
Proof. split; [apply _|done|intros x y [z ->]; by exists (Some z)]. Qed.
Lemma op_is_Some mx my : is_Some (mx ⋅ my) ↔ is_Some mx ∨ is_Some my.
Proof.
destruct mx, my; rewrite /op /option_op /= -!not_eq_None_Some; naive_solver.
Qed.
Lemma option_op_positive_dist_l n mx my : mx ⋅ my ≡{n}≡ None → mx ≡{n}≡ None.
Proof. by destruct mx, my; inversion_clear 1. Qed.
Lemma option_op_positive_dist_r n mx my : mx ⋅ my ≡{n}≡ None → my ≡{n}≡ None.
Proof. by destruct mx, my; inversion_clear 1. Qed.
Global Instance Some_persistent (x : A) : Persistent x → Persistent (Some x).
Proof. by constructor. Qed.
Global Instance option_persistent (mx : option A) :
(∀ x : A, Persistent x) → Persistent mx.
Proof. intros. destruct mx. apply _. apply cmra_unit_persistent. Qed.
(** Updates *)
Lemma option_updateP (P : A → Prop) (Q : option A → Prop) x :
x ~~>: P → (∀ y, P y → Q (Some y)) → Some x ~~>: Q.
Proof.
intros Hx Hy n [y|] ?.
{ destruct (Hx n y) as (y'&?&?); auto. exists (Some y'); auto. }
destruct (Hx n (core x)) as (y'&?&?); rewrite ?cmra_core_r; auto.
by exists (Some y'); split; [auto|apply cmra_validN_op_l with (core x)].
Qed.
Lemma option_updateP' (P : A → Prop) x :
x ~~>: P → Some x ~~>: λ my, default False my P.
Proof. eauto using option_updateP. Qed.
Lemma option_update x y : x ~~> y → Some x ~~> Some y.
Proof.
rewrite !cmra_update_updateP; eauto using option_updateP with congruence.
Qed.
Lemma option_update_None `{Empty A, !CMRAUnit A} : ∅ ~~> Some ∅.
Proof.
intros n [x|] ?; rewrite /op /cmra_op /validN /cmra_validN /= ?left_id;
auto using cmra_unit_validN.
Qed.
End option.
Arguments optionR : clear implicits.
Instance option_fmap_cmra_monotone {A B : cmraT} (f: A → B) `{!CMRAMonotone f} :
CMRAMonotone (fmap f : option A → option B).
Proof.
split; first apply _.
- intros n [x|] ?; rewrite /cmra_validN //=. by apply (validN_preserving f).
- intros mx my; rewrite !option_included.
intros [->|(x&y&->&->&?)]; simpl; eauto 10 using @included_preserving.
Qed.
Program Definition optionRF (F : rFunctor) : rFunctor := {|
rFunctor_car A B := optionR (rFunctor_car F A B);
rFunctor_map A1 A2 B1 B2 fg := optionC_map (rFunctor_map F fg)
|}.
Next Obligation.
by intros F A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, rFunctor_ne.
Qed.
Next Obligation.
intros F A B x. rewrite /= -{2}(option_fmap_id x).
apply option_fmap_setoid_ext=>y; apply rFunctor_id.
Qed.
Next Obligation.
intros F A1 A2 A3 B1 B2 B3 f g f' g' x. rewrite /= -option_fmap_compose.
apply option_fmap_setoid_ext=>y; apply rFunctor_compose.
Qed.
Instance optionRF_contractive F :
rFunctorContractive F → rFunctorContractive (optionRF F).
Proof.
by intros ? A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, rFunctor_contractive.
Qed.
algebra/cofe.v
View file @ d27b81ff
......@@ -450,6 +450,91 @@ Proof. by intros x y. Qed.
Canonical Structure natC := leibnizC nat.
Canonical Structure boolC := leibnizC bool.
(* Option *)
Section option.
Context {A : cofeT}.
Inductive option_dist' (n : nat) : relation (option A) :=
| Some_dist x y : x ≡{n}≡ y → option_dist' n (Some x) (Some y)
| None_dist : option_dist' n None None.
Instance option_dist : Dist (option A) := option_dist'.
Lemma dist_option_Forall2 n mx my : mx ≡{n}≡ my ↔ option_Forall2 (dist n) mx my.
Proof. split; destruct 1; constructor; auto. Qed.
Program Definition option_chain (c : chain (option A)) (x : A) : chain A :=
{| chain_car n := from_option x (c n) |}.
Next Obligation. intros c x n i ?; simpl. by destruct (chain_cauchy c n i). Qed.
Instance option_compl : Compl (option A) := λ c,
match c 0 with Some x => Some (compl (option_chain c x)) | None => None end.
Definition option_cofe_mixin : CofeMixin (option A).
Proof.
split.
- intros mx my; split; [by destruct 1; constructor; apply equiv_dist|].
intros Hxy; destruct (Hxy 0); constructor; apply equiv_dist.
by intros n; feed inversion (Hxy n).
- intros n; split.
+ by intros [x|]; constructor.
+ by destruct 1; constructor.
+ destruct 1; inversion_clear 1; constructor; etrans; eauto.
- destruct 1; constructor; by apply dist_S.
- intros n c; rewrite /compl /option_compl.
feed inversion (chain_cauchy c 0 n); first auto with lia; constructor.
rewrite (conv_compl n (option_chain c _)) /=. destruct (c n); naive_solver.
Qed.
Canonical Structure optionC := CofeT (option A) option_cofe_mixin.
Global Instance option_discrete : Discrete A → Discrete optionC.
Proof. destruct 2; constructor; by apply (timeless _). Qed.
Global Instance Some_ne : Proper (dist n ==> dist n) (@Some A).
Proof. by constructor. Qed.
Global Instance is_Some_ne n : Proper (dist n ==> iff) (@is_Some A).
Proof. destruct 1; split; eauto. Qed.
Global Instance Some_dist_inj : Inj (dist n) (dist n) (@Some A).
Proof. by inversion_clear 1. Qed.
Global Instance from_option_ne n :
Proper (dist n ==> dist n ==> dist n) (@from_option A).
Proof. by destruct 2. Qed.
Global Instance None_timeless : Timeless (@None A).
Proof. inversion_clear 1; constructor. Qed.
Global Instance Some_timeless x : Timeless x → Timeless (Some x).
Proof. by intros ?; inversion_clear 1; constructor; apply timeless. Qed.
End option.
Arguments optionC : clear implicits.
Instance option_fmap_ne {A B : cofeT} (f : A → B) n:
Proper (dist n ==> dist n) f → Proper (dist n==>dist n) (fmap (M:=option) f).
Proof. by intros Hf; destruct 1; constructor; apply Hf. Qed.
Definition optionC_map {A B} (f : A -n> B) : optionC A -n> optionC B :=
CofeMor (fmap f : optionC A → optionC B).
Instance optionC_map_ne A B n : Proper (dist n ==> dist n) (@optionC_map A B).
Proof. by intros f f' Hf []; constructor; apply Hf. Qed.
Program Definition optionCF (F : cFunctor) : cFunctor := {|
cFunctor_car A B := optionC (cFunctor_car F A B);
cFunctor_map A1 A2 B1 B2 fg := optionC_map (cFunctor_map F fg)
|}.
Next Obligation.
by intros F A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, cFunctor_ne.
Qed.
Next Obligation.
intros F A B x. rewrite /= -{2}(option_fmap_id x).
apply option_fmap_setoid_ext=>y; apply cFunctor_id.
Qed.
Next Obligation.
intros F A1 A2 A3 B1 B2 B3 f g f' g' x. rewrite /= -option_fmap_compose.
apply option_fmap_setoid_ext=>y; apply cFunctor_compose.
Qed.
Instance optionCF_contractive F :
cFunctorContractive F → cFunctorContractive (optionCF F).
Proof.
by intros ? A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, cFunctor_contractive.
Qed.
(** Later *)
Inductive later (A : Type) : Type := Next { later_car : A }.
Add Printing Constructor later.
......
algebra/gmap.v
View file @ d27b81ff
From iris.algebra Require Export cmra option.
From iris.algebra Require Export cmra.
From iris.prelude Require Export gmap.
From iris.algebra Require Import upred.
......
algebra/list.v
View file @ d27b81ff
From iris.algebra Require Import cmra option.
From iris.prelude Require Import list.
From iris.algebra Require Export cmra.
From iris.prelude Require Export list.
From iris.algebra Require Import upred.
Section cofe.
......
algebra/option.v deleted 100644 → 0
View file @ a3d0a338
From iris.algebra Require Export cmra.
From iris.algebra Require Import upred.
(* COFE *)
Section cofe.
Context {A : cofeT}.
Inductive option_dist' (n : nat) : relation (option A) :=
| Some_dist x y : x ≡{n}≡ y → option_dist' n (Some x) (Some y)
| None_dist : option_dist' n None None.
Instance option_dist : Dist (option A) := option_dist'.
Lemma dist_option_Forall2 n mx my : mx ≡{n}≡ my ↔ option_Forall2 (dist n) mx my.
Proof. split; destruct 1; constructor; auto. Qed.
Program Definition option_chain (c : chain (option A)) (x : A) : chain A :=
{| chain_car n := from_option x (c n) |}.
Next Obligation. intros c x n i ?; simpl. by destruct (chain_cauchy c n i). Qed.
Instance option_compl : Compl (option A) := λ c,
match c 0 with Some x => Some (compl (option_chain c x)) | None => None end.
Definition option_cofe_mixin : CofeMixin (option A).
Proof.
split.
- intros mx my; split; [by destruct 1; constructor; apply equiv_dist|].
intros Hxy; destruct (Hxy 0); constructor; apply equiv_dist.
by intros n; feed inversion (Hxy n).
- intros n; split.
+ by intros [x|]; constructor.
+ by destruct 1; constructor.
+ destruct 1; inversion_clear 1; constructor; etrans; eauto.
- destruct 1; constructor; by apply dist_S.
- intros n c; rewrite /compl /option_compl.
feed inversion (chain_cauchy c 0 n); first auto with lia; constructor.
rewrite (conv_compl n (option_chain c _)) /=. destruct (c n); naive_solver.
Qed.
Canonical Structure optionC := CofeT (option A) option_cofe_mixin.
Global Instance option_discrete : Discrete A → Discrete optionC.
Proof. destruct 2; constructor; by apply (timeless _). Qed.
Global Instance Some_ne : Proper (dist n ==> dist n) (@Some A).
Proof. by constructor. Qed.
Global Instance is_Some_ne n : Proper (dist n ==> iff) (@is_Some A).
Proof. destruct 1; split; eauto. Qed.
Global Instance Some_dist_inj : Inj (dist n) (dist n) (@Some A).
Proof. by inversion_clear 1. Qed.
Global Instance from_option_ne n :
Proper (dist n ==> dist n ==> dist n) (@from_option A).
Proof. by destruct 2. Qed.
Global Instance None_timeless : Timeless (@None A).
Proof. inversion_clear 1; constructor. Qed.
Global Instance Some_timeless x : Timeless x → Timeless (Some x).
Proof. by intros ?; inversion_clear 1; constructor; apply timeless. Qed.
End cofe.
Arguments optionC : clear implicits.
(* CMRA *)
Section cmra.
Context {A : cmraT}.
Instance option_valid : Valid (option A) := λ mx,
match mx with Some x => ✓ x | None => True end.
Instance option_validN : ValidN (option A) := λ n mx,
match mx with Some x => ✓{n} x | None => True end.
Global Instance option_empty : Empty (option A) := None.
Instance option_core : Core (option A) := fmap core.
Instance option_op : Op (option A) := union_with (λ x y, Some (x ⋅ y)).
Definition Some_valid a : ✓ Some a ↔ ✓ a := reflexivity _.
Definition Some_op a b : Some (a ⋅ b) = Some a ⋅ Some b := eq_refl.
Lemma option_included (mx my : option A) :
mx ≼ my ↔ mx = None ∨ ∃ x y, mx = Some x ∧ my = Some y ∧ x ≼ y.
Proof.
split.
- intros [mz Hmz].
destruct mx as [x|]; [right|by left].
destruct my as [y|]; [exists x, y|destruct mz; inversion_clear Hmz].
destruct mz as [z|]; inversion_clear Hmz; split_and?; auto;
setoid_subst; eauto using cmra_included_l.
- intros [->|(x&y&->&->&z&Hz)]; try (by exists my; destruct my; constructor).
by exists (Some z); constructor.
Qed.
Definition option_cmra_mixin : CMRAMixin (option A).
Proof.
split.
- by intros n [x|]; destruct 1; constructor; cofe_subst.
- by destruct 1; constructor; cofe_subst.
- by destruct 1; rewrite /validN /option_validN //=; cofe_subst.
- intros [x|]; [apply cmra_valid_validN|done].
- intros n [x|]; unfold validN, option_validN; eauto using cmra_validN_S.
- intros [x|] [y|] [z|]; constructor; rewrite ?assoc; auto.
- intros [x|] [y|]; constructor; rewrite 1?comm; auto.
- by intros [x|]; constructor; rewrite cmra_core_l.
- by intros [x|]; constructor; rewrite cmra_core_idemp.
- intros mx my; rewrite !option_included ;intros [->|(x&y&->&->&?)]; auto.
right; exists (core x), (core y); eauto using cmra_core_preserving.
- intros n [x|] [y|]; rewrite /validN /option_validN /=;
eauto using cmra_validN_op_l.
- intros n mx my1 my2.
destruct mx as [x|], my1 as [y1|], my2 as [y2|]; intros Hx Hx';
try (by exfalso; inversion Hx'; auto).
+ destruct (cmra_extend n x y1 y2) as ([z1 z2]&?&?&?); auto.
{ by inversion_clear Hx'. }
by exists (Some z1, Some z2); repeat constructor.
+ by exists (Some x,None); inversion Hx'; repeat constructor.
+ by exists (None,Some x); inversion Hx'; repeat constructor.
+ exists (None,None); repeat constructor.
Qed.
Canonical Structure optionR :=
CMRAT (option A) option_cofe_mixin option_cmra_mixin.
Global Instance option_cmra_unit : CMRAUnit optionR.
Proof. split. done. by intros []. by inversion_clear 1. Qed.
Global Instance option_cmra_discrete : CMRADiscrete A → CMRADiscrete optionR.
Proof. split; [apply _|]. by intros [x|]; [apply (cmra_discrete_valid x)|]. Qed.
(** Misc *)
Global Instance Some_cmra_monotone : CMRAMonotone Some.
Proof. split; [apply _|done|intros x y [z ->]; by exists (Some z)]. Qed.
Lemma op_is_Some mx my : is_Some (mx ⋅ my) ↔ is_Some mx ∨ is_Some my.
Proof.
destruct mx, my; rewrite /op /option_op /= -!not_eq_None_Some; naive_solver.
Qed.
Lemma option_op_positive_dist_l n mx my : mx ⋅ my ≡{n}≡ None → mx ≡{n}≡ None.
Proof. by destruct mx, my; inversion_clear 1. Qed.
Lemma option_op_positive_dist_r n mx my : mx ⋅ my ≡{n}≡ None → my ≡{n}≡ None.
Proof. by destruct mx, my; inversion_clear 1. Qed.
Global Instance Some_persistent (x : A) : Persistent x → Persistent (Some x).
Proof. by constructor. Qed.
Global Instance option_persistent (mx : option A) :
(∀ x : A, Persistent x) → Persistent mx.
Proof. intros. destruct mx. apply _. apply cmra_unit_persistent. Qed.
(** Internalized properties *)
Lemma option_equivI {M} (mx my : option A) :
(mx ≡ my) ⊣⊢ (match mx, my with
| Some x, Some y => x ≡ y | None, None => True | _, _ => False
end : uPred M).
Proof.
uPred.unseal. do 2 split. by destruct 1. by destruct mx, my; try constructor.
Qed.
Lemma option_validI {M} (mx : option A) :
(✓ mx) ⊣⊢ (match mx with Some x => ✓ x | None => True end : uPred M).
Proof. uPred.unseal. by destruct mx. Qed.
(** Updates *)
Lemma option_updateP (P : A → Prop) (Q : option A → Prop) x :
x ~~>: P → (∀ y, P y → Q (Some y)) → Some x ~~>: Q.
Proof.
intros Hx Hy n [y|] ?.
{ destruct (Hx n y) as (y'&?&?); auto. exists (Some y'); auto. }
destruct (Hx n (core x)) as (y'&?&?); rewrite ?cmra_core_r; auto.
by exists (Some y'); split; [auto|apply cmra_validN_op_l with (core x)].
Qed.
Lemma option_updateP' (P : A → Prop) x :
x ~~>: P → Some x ~~>: λ my, default False my P.
Proof. eauto using option_updateP. Qed.
Lemma option_update x y : x ~~> y → Some x ~~> Some y.
Proof.
rewrite !cmra_update_updateP; eauto using option_updateP with congruence.
Qed.
Lemma option_update_None `{Empty A, !CMRAUnit A} : ∅ ~~> Some ∅.
Proof.
intros n [x|] ?; rewrite /op /cmra_op /validN /cmra_validN /= ?left_id;
auto using cmra_unit_validN.
Qed.
End cmra.
Arguments optionR : clear implicits.
(** Functor *)
Instance option_fmap_ne {A B : cofeT} (f : A → B) n:
Proper (dist n ==> dist n) f → Proper (dist n==>dist n) (fmap (M:=option) f).
Proof. by intros Hf; destruct 1; constructor; apply Hf. Qed.
Instance option_fmap_cmra_monotone {A B : cmraT} (f: A → B) `{!CMRAMonotone f} :
CMRAMonotone (fmap f : option A → option B).
Proof.
split; first apply _.
- intros n [x|] ?; rewrite /cmra_validN //=. by apply (validN_preserving f).
- intros mx my; rewrite !option_included.
intros [->|(x&y&->&->&?)]; simpl; eauto 10 using @included_preserving.
Qed.
Definition optionC_map {A B} (f : A -n> B) : optionC A -n> optionC B :=
CofeMor (fmap f : optionC A → optionC B).
Instance optionC_map_ne A B n : Proper (dist n ==> dist n) (@optionC_map A B).
Proof. by intros f f' Hf []; constructor; apply Hf. Qed.
Program Definition optionCF (F : cFunctor) : cFunctor := {|
cFunctor_car A B := optionC (cFunctor_car F A B);
cFunctor_map A1 A2 B1 B2 fg := optionC_map (cFunctor_map F fg)
|}.
Next Obligation.
by intros F A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, cFunctor_ne.
Qed.
Next Obligation.
intros F A B x. rewrite /= -{2}(option_fmap_id x).
apply option_fmap_setoid_ext=>y; apply cFunctor_id.
Qed.
Next Obligation.
intros F A1 A2 A3 B1 B2 B3 f g f' g' x. rewrite /= -option_fmap_compose.
apply option_fmap_setoid_ext=>y; apply cFunctor_compose.
Qed.
Instance optionCF_contractive F :
cFunctorContractive F → cFunctorContractive (optionCF F).
Proof.
by intros ? A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, cFunctor_contractive.
Qed.
Program Definition optionRF (F : rFunctor) : rFunctor := {|
rFunctor_car A B := optionR (rFunctor_car F A B);
rFunctor_map A1 A2 B1 B2 fg := optionC_map (rFunctor_map F fg)
|}.
Next Obligation.
by intros F A1 A2 B1 B2 n f g Hfg; apply optionC_map_ne, rFunctor_ne.
Qed.
Next Obligation.
intros F A B x. rewrite /= -{2}(option_fmap_id x).
apply option_fmap_setoid_ext=>y; apply rFunctor_id.