Definition leftc := false.Definition rightc := true.Ltac pairInv := 
  match goal with
    | [H : (_, _) = (_, _) |- _] => 
      inversion H; clear H; subst
  end.Ltac simp_ret := 
  match goal with
    | [H : In _ (getSupport (ret _)) |- _] => 
      simpl in H; intuition; pairInv
  end.Ltac wftac_one :=
  match goal with
    | [|- well_formed_comp (Bind _ _) ] => eapply well_formed_Bind
    | [|- well_formed_comp (Ret _ _ ) ] => eapply well_formed_Ret
    | [|- well_formed_comp (Rnd _) ] => eapply well_formed_Rnd
    | [|- well_formed_comp (let (_,_) := ?y in _ ) ] => destruct y
    | [|- well_formed_comp (if ?x then _ else _) ] => destruct x
    | [|- @well_formed_oc _ _ _ _ ] => econstructor
  end.Ltac wftac :=
  repeat (unfold setLet; intuition; eauto with wftac; try simp_ret; wftac_one).Ltac destructLet_1 :=
  match goal with
    | [|- context[match ?x with | pair _ _ => _ end]] => destruct x
  end.Ltac destructLet := repeat destructLet_1.(* tactics *)

Ltac dist_ret_l :=
  match goal with
      | [ |- ?rel (evalDist (Bind (Ret _ _) ?f) _) _ ] => 
        eapply trans; [eapply (@evalDist_left_ident rel _ _ _ _ f); eauto with typeclass_instances | idtac]
  end.Ltac dist_ret_r :=
  match goal with
      | [ |- ?rel _ (evalDist (Bind (Ret _ _) ?f) _) ] => 
        eapply trans; [idtac | eapply (@evalDist_left_ident (Basics.flip rel) _ _ _ _ f);  eauto with typeclass_instances]
  end.Ltac dist_simp_1 := unfold setLet; try dist_ret_l; try dist_ret_r; cbv beta iota; destructLet.(* we only want to destruct identifiers, so we must cbv first*)

Ltac dist_simp := repeat dist_simp_1.Ltac dist_simp_weak_1 := unfold setLet; try dist_ret_l.Ltac dist_simp_weak := repeat dist_simp_weak_1.Ltac dist_inline_l :=
  match goal with
      | [ |- ?rel _ _ ] => 
        eapply trans; [ eapply (@evalDist_assoc rel);  eauto with typeclass_instances | idtac]
  end; dist_simp_weak.Ltac dist_inline_r :=
  match goal with
      | [ |- ?rel _ _ ] => 
        eapply trans; [ idtac | eapply (@evalDist_assoc (Basics.flip rel));  eauto with typeclass_instances]
  end; dist_simp_weak.Ltac dist_inline s :=
  match s with
    | leftc => dist_inline_l
    | rightc => dist_inline_r
  end.Ltac dist_ret s :=
  match s with
      | leftc => dist_ret_l
      | rightc => dist_ret_r
  end.Ltac dist_inline_first_1 := try dist_inline_l; try dist_inline_r.Ltac dist_inline_first := repeat (dist_simp_weak_1; dist_inline_first_1).Ltac dist_swap_l :=
  match goal with
    | [ |- ?rel (evalDist (Bind ?c1 (fun x => (Bind ?c2 _))) _) _ ] => 
      eapply trans; [eapply (@evalDist_commute rel _ _ c1 c2); eauto with typeclass_instances | idtac]
  end.Ltac dist_swap_r :=
  match goal with
    | [ |- ?rel _ (evalDist (Bind ?c1 (fun x => (Bind ?c2 _))) _) ] => 
      eapply trans; [ idtac | eapply (@evalDist_commute (Basics.flip rel) _ _ c1 c2);  eauto with typeclass_instances]
  end; dist_simp_weak.Ltac dist_swap side :=
  match side with
    | leftc => dist_swap_l
    | rightc => dist_swap_r
  end.Ltac dist_at_l tac line :=
  match line with
    | O => tac leftc
    | S ?line' => eapply trans; [ eapply rel_seq; intuition; dist_at_l tac line'; eapply refl; eapply eqRat_refl | idtac]
  end; dist_simp_weak.Ltac dist_at_r tac line :=
  match line with
    | O => tac rightc
    | S ?line' =>
      eapply trans; [idtac |
                     eapply rel_seq; [ intuition | intuition; (dist_at_r tac line'); eapply refl; eapply eqRat_refl] ] 
  end; dist_simp.Ltac dist_at tac side line :=
  match side with
    | leftc => dist_at_l tac (line)%nat
    | rightc => dist_at_r tac (line)%nat
  end.Ltac dist_skip :=
  eapply evalDist_seq; [ idtac | eauto with typeclass_instances | idtac] ; intuition; subst; dist_simp_weak; intuition.Ltac dist_irr_l :=
  eapply evalDist_irr_l; [  eauto with typeclass_instances | simpl | idtac] ; intuition; dist_simp_weak.Ltac dist_irr_r :=
  eapply evalDist_irr_r; [  eauto with typeclass_instances | simpl | idtac] ; intuition; dist_simp_weak.

Lemma eqb_true_False : forall (A : Set)(eqd : EqDec A) (a1 a2 : A), (eqb a1 a2 = true -> False) -> a1 <> a2.