Lvc.paco.paco2

Require Export paconotation pacotac pacodef pacotacuser.
Set Implicit Arguments.

Section Arg2_1.

Definition monotone2 T0 T1 (gf: rel2 T0 T1 → rel2 T0 T1) :=
  ∀ x0 x1 r r´ (IN: gf r x0 x1) (LE: r <2= r´), gf r´ x0 x1.

Variable T0 : Type.
Variable T1 : ∀ (x0: @T0), Type.
Variable gf : rel2 T0 T1 → rel2 T0 T1.
Implicit Arguments gf [].

Theorem paco2_acc: ∀
  l r (OBG: ∀ rr (INC: r <2= rr) (CIH: l <_paco_2= rr), l <_paco_2= paco2 gf rr),
  l <2= paco2 gf r.
Proof.
  intros; assert (SIM: paco2 gf (r \2/ l) x0 x1) by eauto.
  clear PR; repeat (try left; do 3 paco_revert; paco_cofix_auto).
Qed.

Theorem paco2_mon: monotone2 (paco2 gf).
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_mult_strong: ∀ r,
  paco2 gf (paco2 gf r \2/ r) <2= paco2 gf r.
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Corollary paco2_mult: ∀ r,
  paco2 gf (paco2 gf r) <2= paco2 gf r.
Proof. intros; eapply paco2_mult_strong, paco2_mon; eauto. Qed.

Theorem paco2_fold: ∀ r,
  gf (paco2 gf r \2/ r) <2= paco2 gf r.
Proof. intros; econstructor; [ |eauto]; eauto. Qed.

Theorem paco2_unfold: ∀ (MON: monotone2 gf) r,
  paco2 gf r <2= gf (paco2 gf r \2/ r).
Proof. unfold monotone2; intros; destruct PR; eauto. Qed.

End Arg2_1.

Hint Unfold monotone2.
Hint Resolve paco2_fold.

Implicit Arguments paco2_acc [ T0 T1 ].
Implicit Arguments paco2_mon [ T0 T1 ].
Implicit Arguments paco2_mult_strong [ T0 T1 ].
Implicit Arguments paco2_mult [ T0 T1 ].
Implicit Arguments paco2_fold [ T0 T1 ].
Implicit Arguments paco2_unfold [ T0 T1 ].

Instance paco2_inst T0 T1 (gf : rel2 T0 T1→_) r x0 x1 : paco_class (paco2 gf r x0 x1) :=
{ pacoacc := paco2_acc gf;
  pacomult := paco2_mult gf;
  pacofold := paco2_fold gf;
  pacounfold := paco2_unfold gf }.

Section Arg2_2.

Definition monotone2_2 T0 T1 (gf: rel2 T0 T1 → rel2 T0 T1 → rel2 T0 T1) :=
  ∀ x0 x1 r_0 r_1 r´_0 r´_1 (IN: gf r_0 r_1 x0 x1) (LE_0: r_0 <2= r´_0)(LE_1: r_1 <2= r´_1), gf r´_0 r´_1 x0 x1.

Variable T0 : Type.
Variable T1 : ∀ (x0: @T0), Type.
Variable gf_0 gf_1 : rel2 T0 T1 → rel2 T0 T1 → rel2 T0 T1.
Implicit Arguments gf_0 [].
Implicit Arguments gf_1 [].

Theorem paco2_2_0_acc: ∀
  l r_0 r_1 (OBG: ∀ rr (INC: r_0 <2= rr) (CIH: l <_paco_2= rr), l <_paco_2= paco2_2_0 gf_0 gf_1 rr r_1),
  l <2= paco2_2_0 gf_0 gf_1 r_0 r_1.
Proof.
  intros; assert (SIM: paco2_2_0 gf_0 gf_1 (r_0 \2/ l) r_1 x0 x1) by eauto.
  clear PR; repeat (try left; do 3 paco_revert; paco_cofix_auto).
Qed.

Theorem paco2_2_1_acc: ∀
  l r_0 r_1 (OBG: ∀ rr (INC: r_1 <2= rr) (CIH: l <_paco_2= rr), l <_paco_2= paco2_2_1 gf_0 gf_1 r_0 rr),
  l <2= paco2_2_1 gf_0 gf_1 r_0 r_1.
Proof.
  intros; assert (SIM: paco2_2_1 gf_0 gf_1 r_0 (r_1 \2/ l) x0 x1) by eauto.
  clear PR; repeat (try left; do 3 paco_revert; paco_cofix_auto).
Qed.

Theorem paco2_2_0_mon: monotone2_2 (paco2_2_0 gf_0 gf_1).
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_2_1_mon: monotone2_2 (paco2_2_1 gf_0 gf_1).
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_2_0_mult_strong: ∀ r_0 r_1,
  paco2_2_0 gf_0 gf_1 (paco2_2_0 gf_0 gf_1 r_0 r_1 \2/ r_0) (paco2_2_1 gf_0 gf_1 r_0 r_1 \2/ r_1) <2= paco2_2_0 gf_0 gf_1 r_0 r_1.
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_2_1_mult_strong: ∀ r_0 r_1,
  paco2_2_1 gf_0 gf_1 (paco2_2_0 gf_0 gf_1 r_0 r_1 \2/ r_0) (paco2_2_1 gf_0 gf_1 r_0 r_1 \2/ r_1) <2= paco2_2_1 gf_0 gf_1 r_0 r_1.
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Corollary paco2_2_0_mult: ∀ r_0 r_1,
  paco2_2_0 gf_0 gf_1 (paco2_2_0 gf_0 gf_1 r_0 r_1) (paco2_2_1 gf_0 gf_1 r_0 r_1) <2= paco2_2_0 gf_0 gf_1 r_0 r_1.
Proof. intros; eapply paco2_2_0_mult_strong, paco2_2_0_mon; eauto. Qed.

Corollary paco2_2_1_mult: ∀ r_0 r_1,
  paco2_2_1 gf_0 gf_1 (paco2_2_0 gf_0 gf_1 r_0 r_1) (paco2_2_1 gf_0 gf_1 r_0 r_1) <2= paco2_2_1 gf_0 gf_1 r_0 r_1.
Proof. intros; eapply paco2_2_1_mult_strong, paco2_2_1_mon; eauto. Qed.

Theorem paco2_2_0_fold: ∀ r_0 r_1,
  gf_0 (paco2_2_0 gf_0 gf_1 r_0 r_1 \2/ r_0) (paco2_2_1 gf_0 gf_1 r_0 r_1 \2/ r_1) <2= paco2_2_0 gf_0 gf_1 r_0 r_1.
Proof. intros; econstructor; [ | |eauto]; eauto. Qed.

Theorem paco2_2_1_fold: ∀ r_0 r_1,
  gf_1 (paco2_2_0 gf_0 gf_1 r_0 r_1 \2/ r_0) (paco2_2_1 gf_0 gf_1 r_0 r_1 \2/ r_1) <2= paco2_2_1 gf_0 gf_1 r_0 r_1.
Proof. intros; econstructor; [ | |eauto]; eauto. Qed.

Theorem paco2_2_0_unfold: ∀ (MON: monotone2_2 gf_0) (MON: monotone2_2 gf_1) r_0 r_1,
  paco2_2_0 gf_0 gf_1 r_0 r_1 <2= gf_0 (paco2_2_0 gf_0 gf_1 r_0 r_1 \2/ r_0) (paco2_2_1 gf_0 gf_1 r_0 r_1 \2/ r_1).
Proof. unfold monotone2_2; intros; destruct PR; eauto. Qed.

Theorem paco2_2_1_unfold: ∀ (MON: monotone2_2 gf_0) (MON: monotone2_2 gf_1) r_0 r_1,
  paco2_2_1 gf_0 gf_1 r_0 r_1 <2= gf_1 (paco2_2_0 gf_0 gf_1 r_0 r_1 \2/ r_0) (paco2_2_1 gf_0 gf_1 r_0 r_1 \2/ r_1).
Proof. unfold monotone2_2; intros; destruct PR; eauto. Qed.

End Arg2_2.

Hint Unfold monotone2_2.
Hint Resolve paco2_2_0_fold.
Hint Resolve paco2_2_1_fold.

Implicit Arguments paco2_2_0_acc [ T0 T1 ].
Implicit Arguments paco2_2_1_acc [ T0 T1 ].
Implicit Arguments paco2_2_0_mon [ T0 T1 ].
Implicit Arguments paco2_2_1_mon [ T0 T1 ].
Implicit Arguments paco2_2_0_mult_strong [ T0 T1 ].
Implicit Arguments paco2_2_1_mult_strong [ T0 T1 ].
Implicit Arguments paco2_2_0_mult [ T0 T1 ].
Implicit Arguments paco2_2_1_mult [ T0 T1 ].
Implicit Arguments paco2_2_0_fold [ T0 T1 ].
Implicit Arguments paco2_2_1_fold [ T0 T1 ].
Implicit Arguments paco2_2_0_unfold [ T0 T1 ].
Implicit Arguments paco2_2_1_unfold [ T0 T1 ].

Instance paco2_2_0_inst T0 T1 (gf_0 gf_1 : rel2 T0 T1→_) r_0 r_1 x0 x1 : paco_class (paco2_2_0 gf_0 gf_1 r_0 r_1 x0 x1) :=
{ pacoacc := paco2_2_0_acc gf_0 gf_1;
  pacomult := paco2_2_0_mult gf_0 gf_1;
  pacofold := paco2_2_0_fold gf_0 gf_1;
  pacounfold := paco2_2_0_unfold gf_0 gf_1 }.

Instance paco2_2_1_inst T0 T1 (gf_0 gf_1 : rel2 T0 T1→_) r_0 r_1 x0 x1 : paco_class (paco2_2_1 gf_0 gf_1 r_0 r_1 x0 x1) :=
{ pacoacc := paco2_2_1_acc gf_0 gf_1;
  pacomult := paco2_2_1_mult gf_0 gf_1;
  pacofold := paco2_2_1_fold gf_0 gf_1;
  pacounfold := paco2_2_1_unfold gf_0 gf_1 }.

Section Arg2_3.

Definition monotone2_3 T0 T1 (gf: rel2 T0 T1 → rel2 T0 T1 → rel2 T0 T1 → rel2 T0 T1) :=
  ∀ x0 x1 r_0 r_1 r_2 r´_0 r´_1 r´_2 (IN: gf r_0 r_1 r_2 x0 x1) (LE_0: r_0 <2= r´_0)(LE_1: r_1 <2= r´_1)(LE_2: r_2 <2= r´_2), gf r´_0 r´_1 r´_2 x0 x1.

Variable T0 : Type.
Variable T1 : ∀ (x0: @T0), Type.
Variable gf_0 gf_1 gf_2 : rel2 T0 T1 → rel2 T0 T1 → rel2 T0 T1 → rel2 T0 T1.
Implicit Arguments gf_0 [].
Implicit Arguments gf_1 [].
Implicit Arguments gf_2 [].

Theorem paco2_3_0_acc: ∀
  l r_0 r_1 r_2 (OBG: ∀ rr (INC: r_0 <2= rr) (CIH: l <_paco_2= rr), l <_paco_2= paco2_3_0 gf_0 gf_1 gf_2 rr r_1 r_2),
  l <2= paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof.
  intros; assert (SIM: paco2_3_0 gf_0 gf_1 gf_2 (r_0 \2/ l) r_1 r_2 x0 x1) by eauto.
  clear PR; repeat (try left; do 3 paco_revert; paco_cofix_auto).
Qed.

Theorem paco2_3_1_acc: ∀
  l r_0 r_1 r_2 (OBG: ∀ rr (INC: r_1 <2= rr) (CIH: l <_paco_2= rr), l <_paco_2= paco2_3_1 gf_0 gf_1 gf_2 r_0 rr r_2),
  l <2= paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof.
  intros; assert (SIM: paco2_3_1 gf_0 gf_1 gf_2 r_0 (r_1 \2/ l) r_2 x0 x1) by eauto.
  clear PR; repeat (try left; do 3 paco_revert; paco_cofix_auto).
Qed.

Theorem paco2_3_2_acc: ∀
  l r_0 r_1 r_2 (OBG: ∀ rr (INC: r_2 <2= rr) (CIH: l <_paco_2= rr), l <_paco_2= paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 rr),
  l <2= paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof.
  intros; assert (SIM: paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 (r_2 \2/ l) x0 x1) by eauto.
  clear PR; repeat (try left; do 3 paco_revert; paco_cofix_auto).
Qed.

Theorem paco2_3_0_mon: monotone2_3 (paco2_3_0 gf_0 gf_1 gf_2).
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_3_1_mon: monotone2_3 (paco2_3_1 gf_0 gf_1 gf_2).
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_3_2_mon: monotone2_3 (paco2_3_2 gf_0 gf_1 gf_2).
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_3_0_mult_strong: ∀ r_0 r_1 r_2,
  paco2_3_0 gf_0 gf_1 gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2) <2= paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_3_1_mult_strong: ∀ r_0 r_1 r_2,
  paco2_3_1 gf_0 gf_1 gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2) <2= paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Theorem paco2_3_2_mult_strong: ∀ r_0 r_1 r_2,
  paco2_3_2 gf_0 gf_1 gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2) <2= paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. paco_cofix_auto; repeat (left; do 3 paco_revert; paco_cofix_auto). Qed.

Corollary paco2_3_0_mult: ∀ r_0 r_1 r_2,
  paco2_3_0 gf_0 gf_1 gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2) <2= paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. intros; eapply paco2_3_0_mult_strong, paco2_3_0_mon; eauto. Qed.

Corollary paco2_3_1_mult: ∀ r_0 r_1 r_2,
  paco2_3_1 gf_0 gf_1 gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2) <2= paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. intros; eapply paco2_3_1_mult_strong, paco2_3_1_mon; eauto. Qed.

Corollary paco2_3_2_mult: ∀ r_0 r_1 r_2,
  paco2_3_2 gf_0 gf_1 gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2) <2= paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. intros; eapply paco2_3_2_mult_strong, paco2_3_2_mon; eauto. Qed.

Theorem paco2_3_0_fold: ∀ r_0 r_1 r_2,
  gf_0 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2) <2= paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. intros; econstructor; [ | | |eauto]; eauto. Qed.

Theorem paco2_3_1_fold: ∀ r_0 r_1 r_2,
  gf_1 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2) <2= paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. intros; econstructor; [ | | |eauto]; eauto. Qed.

Theorem paco2_3_2_fold: ∀ r_0 r_1 r_2,
  gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2) <2= paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2.
Proof. intros; econstructor; [ | | |eauto]; eauto. Qed.

Theorem paco2_3_0_unfold: ∀ (MON: monotone2_3 gf_0) (MON: monotone2_3 gf_1) (MON: monotone2_3 gf_2) r_0 r_1 r_2,
  paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 <2= gf_0 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2).
Proof. unfold monotone2_3; intros; destruct PR; eauto. Qed.

Theorem paco2_3_1_unfold: ∀ (MON: monotone2_3 gf_0) (MON: monotone2_3 gf_1) (MON: monotone2_3 gf_2) r_0 r_1 r_2,
  paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 <2= gf_1 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2).
Proof. unfold monotone2_3; intros; destruct PR; eauto. Qed.

Theorem paco2_3_2_unfold: ∀ (MON: monotone2_3 gf_0) (MON: monotone2_3 gf_1) (MON: monotone2_3 gf_2) r_0 r_1 r_2,
  paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 <2= gf_2 (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_0) (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_1) (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 \2/ r_2).
Proof. unfold monotone2_3; intros; destruct PR; eauto. Qed.

End Arg2_3.

Hint Unfold monotone2_3.
Hint Resolve paco2_3_0_fold.
Hint Resolve paco2_3_1_fold.
Hint Resolve paco2_3_2_fold.

Implicit Arguments paco2_3_0_acc [ T0 T1 ].
Implicit Arguments paco2_3_1_acc [ T0 T1 ].
Implicit Arguments paco2_3_2_acc [ T0 T1 ].
Implicit Arguments paco2_3_0_mon [ T0 T1 ].
Implicit Arguments paco2_3_1_mon [ T0 T1 ].
Implicit Arguments paco2_3_2_mon [ T0 T1 ].
Implicit Arguments paco2_3_0_mult_strong [ T0 T1 ].
Implicit Arguments paco2_3_1_mult_strong [ T0 T1 ].
Implicit Arguments paco2_3_2_mult_strong [ T0 T1 ].
Implicit Arguments paco2_3_0_mult [ T0 T1 ].
Implicit Arguments paco2_3_1_mult [ T0 T1 ].
Implicit Arguments paco2_3_2_mult [ T0 T1 ].
Implicit Arguments paco2_3_0_fold [ T0 T1 ].
Implicit Arguments paco2_3_1_fold [ T0 T1 ].
Implicit Arguments paco2_3_2_fold [ T0 T1 ].
Implicit Arguments paco2_3_0_unfold [ T0 T1 ].
Implicit Arguments paco2_3_1_unfold [ T0 T1 ].
Implicit Arguments paco2_3_2_unfold [ T0 T1 ].

Instance paco2_3_0_inst T0 T1 (gf_0 gf_1 gf_2 : rel2 T0 T1→_) r_0 r_1 r_2 x0 x1 : paco_class (paco2_3_0 gf_0 gf_1 gf_2 r_0 r_1 r_2 x0 x1) :=
{ pacoacc := paco2_3_0_acc gf_0 gf_1 gf_2;
  pacomult := paco2_3_0_mult gf_0 gf_1 gf_2;
  pacofold := paco2_3_0_fold gf_0 gf_1 gf_2;
  pacounfold := paco2_3_0_unfold gf_0 gf_1 gf_2 }.

Instance paco2_3_1_inst T0 T1 (gf_0 gf_1 gf_2 : rel2 T0 T1→_) r_0 r_1 r_2 x0 x1 : paco_class (paco2_3_1 gf_0 gf_1 gf_2 r_0 r_1 r_2 x0 x1) :=
{ pacoacc := paco2_3_1_acc gf_0 gf_1 gf_2;
  pacomult := paco2_3_1_mult gf_0 gf_1 gf_2;
  pacofold := paco2_3_1_fold gf_0 gf_1 gf_2;
  pacounfold := paco2_3_1_unfold gf_0 gf_1 gf_2 }.

Instance paco2_3_2_inst T0 T1 (gf_0 gf_1 gf_2 : rel2 T0 T1→_) r_0 r_1 r_2 x0 x1 : paco_class (paco2_3_2 gf_0 gf_1 gf_2 r_0 r_1 r_2 x0 x1) :=
{ pacoacc := paco2_3_2_acc gf_0 gf_1 gf_2;
  pacomult := paco2_3_2_mult gf_0 gf_1 gf_2;
  pacofold := paco2_3_2_fold gf_0 gf_1 gf_2;
  pacounfold := paco2_3_2_unfold gf_0 gf_1 gf_2 }.