1 files changed, 56 insertions, 16 deletions

diff --git a/lib/stdlib/src/ordsets.erl b/lib/stdlib/src/ordsets.erl
index 5a1c260703..4a8b1275b2 100644
--- a/lib/stdlib/src/ordsets.erl
+++ b/lib/stdlib/src/ordsets.erl
@@ -40,7 +40,8 @@ new() -> [].
 %% is_set(Term) -> boolean().
 %%  Return 'true' if Set is an ordered set of elements, else 'false'.
 
--spec is_set(term()) -> boolean().
+-spec is_set(Ordset) -> boolean() when
+      Ordset :: term().
 
 is_set([E|Es]) -> is_set(Es, E);
 is_set([]) -> true;
@@ -54,21 +55,26 @@ is_set([], _) -> true.
 %% size(OrdSet) -> int().
 %%  Return the number of elements in OrdSet.
 
--spec size(ordset(_)) -> non_neg_integer().
+-spec size(Ordset) -> non_neg_integer() when
+      Ordset :: ordset(_).
 
 size(S) -> length(S).
 
 %% to_list(OrdSet) -> [Elem].
 %%  Return the elements in OrdSet as a list.
 
--spec to_list(ordset(T)) -> [T].
+-spec to_list(Ordset) -> List when
+      Ordset :: ordset(T),
+      List :: [T].
 
 to_list(S) -> S.
 
 %% from_list([Elem]) -> Set.
 %%  Build an ordered set from the elements in List.
 
--spec from_list([T]) -> ordset(T).
+-spec from_list(List) -> Ordset when
+      List :: [T],
+      Ordset :: ordset(T).
 
 from_list(L) ->
     lists:usort(L).
@@ -76,7 +82,9 @@ from_list(L) ->
 %% is_element(Element, OrdSet) -> boolean().
 %%  Return 'true' if Element is an element of OrdSet, else 'false'.
 
--spec is_element(term(), ordset(_)) -> boolean().
+-spec is_element(Element, Ordset) -> boolean() when
+      Element :: term(),
+      Ordset :: ordset(_).
 
 is_element(E, [H|Es]) when E > H -> is_element(E, Es);
 is_element(E, [H|_]) when E < H -> false;
@@ -86,7 +94,12 @@ is_element(_, []) -> false.
 %% add_element(Element, OrdSet) -> OrdSet.
 %%  Return OrdSet with Element inserted in it.
 
--spec add_element(E, ordset(T)) -> [T | E,...].
+-spec add_element(Element, Ordset1) -> Ordset2 when
+      Element :: E,
+      Ordset1 :: ordset(T),
+      Ordset2 :: ordset(T | E).
+
+%-spec add_element(E, ordset(T)) -> [T | E,...].
 
 add_element(E, [H|Es]) when E > H -> [H|add_element(E, Es)];
 add_element(E, [H|_]=Set) when E < H -> [E|Set];
@@ -96,7 +109,10 @@ add_element(E, []) -> [E].
 %% del_element(Element, OrdSet) -> OrdSet.
 %%  Return OrdSet but with Element removed.
 
--spec del_element(term(), ordset(T)) -> ordset(T).
+-spec del_element(Element, Ordset1) -> Ordset2 when
+      Element :: term(),
+      Ordset1 :: ordset(T),
+      Ordset2 :: ordset(T).
 
 del_element(E, [H|Es]) when E > H -> [H|del_element(E, Es)];
 del_element(E, [H|_]=Set) when E < H -> Set;
@@ -106,7 +122,10 @@ del_element(_, []) -> [].
 %% union(OrdSet1, OrdSet2) -> OrdSet
 %%  Return the union of OrdSet1 and OrdSet2.
 
--spec union(ordset(T1), ordset(T2)) -> ordset(T1 | T2).
+-spec union(Ordset1, Ordset2) -> Ordset3 when
+      Ordset1 :: ordset(T1),
+      Ordset2 :: ordset(T2),
+      Ordset3 :: ordset(T1 | T2).
 
 union([E1|Es1], [E2|_]=Set2) when E1 < E2 ->
     [E1|union(Es1, Set2)];
@@ -120,7 +139,9 @@ union(Es1, []) -> Es1.
 %% union([OrdSet]) -> OrdSet
 %%  Return the union of the list of ordered sets.
 
--spec union([ordset(T)]) -> ordset(T).
+-spec union(OrdsetList) -> Ordset when
+      OrdsetList :: [ordset(T)],
+      Ordset :: ordset(T).
 
 union([S1,S2|Ss]) ->
     union1(union(S1, S2), Ss);
@@ -133,7 +154,10 @@ union1(S1, []) -> S1.
 %% intersection(OrdSet1, OrdSet2) -> OrdSet.
 %%  Return the intersection of OrdSet1 and OrdSet2.
 
--spec intersection(ordset(_), ordset(_)) -> ordset(_).
+-spec intersection(Ordset1, Ordset2) -> Ordset3 when
+      Ordset1 :: ordset(_),
+      Ordset2 :: ordset(_),
+      Ordset3 :: ordset(_).
 
 intersection([E1|Es1], [E2|_]=Set2) when E1 < E2 ->
     intersection(Es1, Set2);
@@ -149,7 +173,9 @@ intersection(_, []) ->
 %% intersection([OrdSet]) -> OrdSet.
 %%  Return the intersection of the list of ordered sets.
 
--spec intersection([ordset(_),...]) -> ordset(_).
+-spec intersection(OrdsetList) -> Ordset when
+      OrdsetList :: [ordset(_),...],
+      Ordset :: ordset(_).
 
 intersection([S1,S2|Ss]) ->
     intersection1(intersection(S1, S2), Ss);
@@ -162,7 +188,9 @@ intersection1(S1, []) -> S1.
 %% is_disjoint(OrdSet1, OrdSet2) -> boolean().
 %%  Check whether OrdSet1 and OrdSet2 are disjoint.
 
--spec is_disjoint(ordset(_), ordset(_)) -> boolean().
+-spec is_disjoint(Ordset1, Ordset2) -> boolean() when
+      Ordset1 :: ordset(_),
+      Ordset2 :: ordset(_).
 
 is_disjoint([E1|Es1], [E2|_]=Set2) when E1 < E2 ->
     is_disjoint(Es1, Set2);
@@ -179,7 +207,10 @@ is_disjoint(_, []) ->
 %%  Return all and only the elements of OrdSet1 which are not also in
 %%  OrdSet2.
 
--spec subtract(ordset(_), ordset(_)) -> ordset(_).
+-spec subtract(Ordset1, Ordset2) -> Ordset3 when
+      Ordset1 :: ordset(_),
+      Ordset2 :: ordset(_),
+      Ordset3 :: ordset(_).
 
 subtract([E1|Es1], [E2|_]=Set2) when E1 < E2 ->
     [E1|subtract(Es1, Set2)];
@@ -194,7 +225,9 @@ subtract(Es1, []) -> Es1.
 %%  Return 'true' when every element of OrdSet1 is also a member of
 %%  OrdSet2, else 'false'.
 
--spec is_subset(ordset(_), ordset(_)) -> boolean().
+-spec is_subset(Ordset1, Ordset2) -> boolean() when
+      Ordset1 :: ordset(_),
+      Ordset2 :: ordset(_).
 
 is_subset([E1|_], [E2|_]) when E1 < E2 ->	%E1 not in Set2
     false;
@@ -208,7 +241,11 @@ is_subset(_, []) -> false.
 %% fold(Fun, Accumulator, OrdSet) -> Accumulator.
 %%  Fold function Fun over all elements in OrdSet and return Accumulator.
 
--spec fold(fun((T, term()) -> term()), term(), ordset(T)) -> term().
+-spec fold(Function, Acc0, Ordset) -> Acc1 when
+      Function :: fun((Element :: T, AccIn :: term()) -> AccOut :: term()),
+      Ordset :: ordset(T),
+      Acc0 :: term(),
+      Acc1 :: term().
 
 fold(F, Acc, Set) ->
     lists:foldl(F, Acc, Set).
@@ -216,7 +253,10 @@ fold(F, Acc, Set) ->
 %% filter(Fun, OrdSet) -> OrdSet.
 %%  Filter OrdSet with Fun.
 
--spec filter(fun((T) -> boolean()), ordset(T)) -> ordset(T).
+-spec filter(Pred, Ordset1) -> Ordset2 when
+      Pred :: fun((Element :: T) -> boolean()),
+      Ordset1 :: ordset(T),
+      Ordset2 :: ordset(T).
 
 filter(F, Set) ->
     lists:filter(F, Set).