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-rw-r--r--lib/stdlib/src/ordsets.erl78
1 files changed, 60 insertions, 18 deletions
diff --git a/lib/stdlib/src/ordsets.erl b/lib/stdlib/src/ordsets.erl
index 05041c15f1..4a8b1275b2 100644
--- a/lib/stdlib/src/ordsets.erl
+++ b/lib/stdlib/src/ordsets.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -26,19 +26,22 @@
-export([subtract/2,is_subset/2]).
-export([fold/3,filter/2]).
+-export_type([ordset/1]).
+
-type ordset(T) :: [T].
%% new() -> Set.
%% Return a new empty ordered set.
--spec new() -> ordset(term()).
+-spec new() -> [].
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;
@@ -52,21 +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).
@@ -74,7 +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;
@@ -84,7 +94,12 @@ is_element(_, []) -> false.
%% add_element(Element, OrdSet) -> OrdSet.
%% Return OrdSet with Element inserted in it.
--spec add_element(term(), ordset(_)) -> ordset(_).
+-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];
@@ -94,7 +109,10 @@ add_element(E, []) -> [E].
%% del_element(Element, OrdSet) -> OrdSet.
%% Return OrdSet but with Element removed.
--spec del_element(term(), ordset(_)) -> ordset(_).
+-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;
@@ -104,7 +122,10 @@ del_element(_, []) -> [].
%% union(OrdSet1, OrdSet2) -> OrdSet
%% Return the union of OrdSet1 and OrdSet2.
--spec union(ordset(_), ordset(_)) -> ordset(_).
+-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)];
@@ -118,7 +139,9 @@ union(Es1, []) -> Es1.
%% union([OrdSet]) -> OrdSet
%% Return the union of the list of ordered sets.
--spec union([ordset(_)]) -> ordset(_).
+-spec union(OrdsetList) -> Ordset when
+ OrdsetList :: [ordset(T)],
+ Ordset :: ordset(T).
union([S1,S2|Ss]) ->
union1(union(S1, S2), Ss);
@@ -131,7 +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);
@@ -147,7 +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);
@@ -160,7 +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);
@@ -177,7 +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)];
@@ -192,7 +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;
@@ -206,7 +241,11 @@ is_subset(_, []) -> false.
%% fold(Fun, Accumulator, OrdSet) -> Accumulator.
%% Fold function Fun over all elements in OrdSet and return Accumulator.
--spec fold(fun((_, _) -> _), _, ordset(_)) -> _.
+-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).
@@ -214,7 +253,10 @@ fold(F, Acc, Set) ->
%% filter(Fun, OrdSet) -> OrdSet.
%% Filter OrdSet with Fun.
--spec filter(fun((_) -> boolean()), ordset(_)) -> ordset(_).
+-spec filter(Pred, Ordset1) -> Ordset2 when
+ Pred :: fun((Element :: T) -> boolean()),
+ Ordset1 :: ordset(T),
+ Ordset2 :: ordset(T).
filter(F, Set) ->
lists:filter(F, Set).