Definition elt := E.t.Definition t := M.t.Implicit Type s : t.Implicit Type x y : elt.Implicit Type f : elt -> bool.Definition In : elt -> t -> Prop := M.In.Definition Equal s s' := forall a : elt, In a s <-> In a s'.Definition Subset s s' := forall a : elt, In a s -> In a s'.Definition Empty s := forall a : elt, ~ In a s.Definition For_all (P : elt -> Prop) s := forall x, In x s -> P x.Definition Exists (P : elt -> Prop) s := exists x, In x s /\ P x.Definition empty : t := M.empty.Definition is_empty : t -> bool := M.is_empty.Definition mem : elt -> t -> bool := M.mem.Definition add : elt -> t -> t := M.add.Definition singleton : elt -> t := M.singleton.Definition remove : elt -> t -> t := M.remove.Definition union : t -> t -> t := M.union.Definition inter : t -> t -> t := M.inter.Definition diff : t -> t -> t := M.diff.Definition eq : t -> t -> Prop := M.eq.Definition eq_dec : forall s s', {eq s s'}+{~eq s s'}:= M.eq_dec.Definition equal : t -> t -> bool := M.equal.Definition subset : t -> t -> bool := M.subset.Definition fold : forall A : Type, (elt -> A -> A) -> t -> A -> A := M.fold.Definition for_all : (elt -> bool) -> t -> bool := M.for_all.Definition exists_ : (elt -> bool) -> t -> bool := M.exists_.Definition filter : (elt -> bool) -> t -> t := M.filter.Definition partition : (elt -> bool) -> t -> t * t:= M.partition.Definition cardinal : t -> nat := M.cardinal.Definition elements : t -> list elt := M.elements.Definition choose : t -> option elt := M.choose.Module MF := MSetFacts.WFacts M.Definition In_1 : forall s x y, E.eq x y -> In x s -> In y s
  := MF.In_1.Definition eq_refl : forall s, eq s s
  := @Equivalence_Reflexive _ _ M.eq_equiv.Definition eq_sym : forall s s', eq s s' -> eq s' s
  := @Equivalence_Symmetric _ _ M.eq_equiv.Definition eq_trans : forall s s' s'', eq s s' -> eq s' s'' -> eq s s''
  := @Equivalence_Transitive _ _ M.eq_equiv.Definition mem_1 : forall s x, In x s -> mem x s = true
  := MF.mem_1.Definition mem_2 : forall s x, mem x s = true -> In x s
  := MF.mem_2.Definition equal_1 : forall s s', Equal s s' -> equal s s' = true
  := MF.equal_1.Definition equal_2 : forall s s', equal s s' = true -> Equal s s'
  := MF.equal_2.Definition subset_1 : forall s s', Subset s s' -> subset s s' = true
  := MF.subset_1.Definition subset_2 : forall s s', subset s s' = true -> Subset s s'
  := MF.subset_2.Definition empty_1 : Empty empty := MF.empty_1.Definition is_empty_1 : forall s, Empty s -> is_empty s = true
  := MF.is_empty_1.Definition is_empty_2 : forall s, is_empty s = true -> Empty s
  := MF.is_empty_2.Definition add_1 : forall s x y, E.eq x y -> In y (add x s)
  := MF.add_1.Definition add_2 : forall s x y, In y s -> In y (add x s)
  := MF.add_2.Definition add_3 : forall s x y, ~ E.eq x y -> In y (add x s) -> In y s
  := MF.add_3.Definition remove_1 : forall s x y, E.eq x y -> ~ In y (remove x s)
  := MF.remove_1.Definition remove_2 : forall s x y, ~ E.eq x y -> In y s -> In y (remove x s)
  := MF.remove_2.Definition remove_3 : forall s x y, In y (remove x s) -> In y s
  := MF.remove_3.Definition union_1 : forall s s' x, In x (union s s') -> In x s \/ In x s'
  := MF.union_1.Definition union_2 : forall s s' x, In x s -> In x (union s s')
  := MF.union_2.Definition union_3 : forall s s' x, In x s' -> In x (union s s')
  := MF.union_3.Definition inter_1 : forall s s' x, In x (inter s s') -> In x s
  := MF.inter_1.Definition inter_2 : forall s s' x, In x (inter s s') -> In x s'
  := MF.inter_2.Definition inter_3 : forall s s' x, In x s -> In x s' -> In x (inter s s')
  := MF.inter_3.Definition diff_1 : forall s s' x, In x (diff s s') -> In x s
  := MF.diff_1.Definition diff_2 : forall s s' x, In x (diff s s') -> ~ In x s'
  := MF.diff_2.Definition diff_3 : forall s s' x, In x s -> ~ In x s' -> In x (diff s s')
  := MF.diff_3.Definition singleton_1 : forall x y, In y (singleton x) -> E.eq x y
  := MF.singleton_1.Definition singleton_2 : forall x y, E.eq x y -> In y (singleton x)
  := MF.singleton_2.Definition fold_1 : forall s (A : Type) (i : A) (f : elt -> A -> A),
   fold f s i = fold_left (fun a e => f e a) (elements s) i
  := MF.fold_1.Definition cardinal_1 : forall s, cardinal s = length (elements s)
  := MF.cardinal_1.Definition filter_1 : forall s x f, compat_bool E.eq f ->
  In x (filter f s) -> In x s
  := MF.filter_1.Definition filter_2 : forall s x f, compat_bool E.eq f ->
  In x (filter f s) -> f x = true
  := MF.filter_2.Definition filter_3 : forall s x f, compat_bool E.eq f ->
  In x s -> f x = true -> In x (filter f s)
  := MF.filter_3.Definition for_all_1 : forall s f, compat_bool E.eq f ->
  For_all (fun x => f x = true) s -> for_all f s = true
  := MF.for_all_1.Definition for_all_2 : forall s f, compat_bool E.eq f ->
  for_all f s = true -> For_all (fun x => f x = true) s
  := MF.for_all_2.Definition exists_1 : forall s f, compat_bool E.eq f ->
  Exists (fun x => f x = true) s -> exists_ f s = true
  := MF.exists_1.Definition exists_2 : forall s f, compat_bool E.eq f ->
  exists_ f s = true -> Exists (fun x => f x = true) s
  := MF.exists_2.Definition partition_1 : forall s f, compat_bool E.eq f ->
  Equal (fst (partition f s)) (filter f s)
  := MF.partition_1.Definition partition_2 : forall s f, compat_bool E.eq f ->
  Equal (snd (partition f s)) (filter (fun x => negb (f x)) s)
  := MF.partition_2.Definition choose_1 : forall s x, choose s = Some x -> In x s
  := MF.choose_1.Definition choose_2 : forall s, choose s = None -> Empty s
  := MF.choose_2.Definition elements_1 : forall s x, In x s -> InA E.eq x (elements s)
  := MF.elements_1.Definition elements_2 : forall s x, InA E.eq x (elements s) -> In x s
  := MF.elements_2.Definition elements_3w : forall s, NoDupA E.eq (elements s)
  := MF.elements_3w.Implicit Type s : t.Implicit Type x y : elt.Definition lt : t -> t -> Prop := M.lt.Definition min_elt : t -> option elt := M.min_elt.Definition max_elt : t -> option elt := M.max_elt.Definition min_elt_1 : forall s x, min_elt s = Some x -> In x s
   := M.min_elt_spec1.Definition min_elt_2 : forall s x y,
   min_elt s = Some x -> In y s -> ~ O.lt y x
   := M.min_elt_spec2.Definition min_elt_3 : forall s, min_elt s = None -> Empty s
   := M.min_elt_spec3.Definition max_elt_1 : forall s x, max_elt s = Some x -> In x s
   := M.max_elt_spec1.Definition max_elt_2 : forall s x y,
   max_elt s = Some x -> In y s -> ~ O.lt x y
   := M.max_elt_spec2.Definition max_elt_3 : forall s, max_elt s = None -> Empty s
   := M.max_elt_spec3.Definition elements_3 : forall s, sort O.lt (elements s)
   := M.elements_spec2.Definition choose_3 : forall s s' x y,
   choose s = Some x -> choose s' = Some y -> Equal s s' -> O.eq x y
   := M.choose_spec3.Definition lt_trans : forall s s' s'', lt s s' -> lt s' s'' -> lt s s''
   := @StrictOrder_Transitive _ _ M.lt_strorder.

Lemma lt_not_eq : forall s s', lt s s' -> ~ eq s s'.