diff options
Diffstat (limited to 'lib/stdlib/src/ordsets.erl')
-rw-r--r-- | lib/stdlib/src/ordsets.erl | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/lib/stdlib/src/ordsets.erl b/lib/stdlib/src/ordsets.erl index 6010b41006..176047079b 100644 --- a/lib/stdlib/src/ordsets.erl +++ b/lib/stdlib/src/ordsets.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2011. All Rights Reserved. +%% Copyright Ericsson AB 1996-2018. All Rights Reserved. %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. @@ -19,7 +19,7 @@ -module(ordsets). --export([new/0,is_set/1,size/1,to_list/1,from_list/1]). +-export([new/0,is_set/1,size/1,is_empty/1,to_list/1,from_list/1]). -export([is_element/2,add_element/2,del_element/2]). -export([union/2,union/1,intersection/2,intersection/1]). -export([is_disjoint/2]). @@ -60,6 +60,13 @@ is_set([], _) -> true. size(S) -> length(S). +%% is_empty(OrdSet) -> boolean(). +%% Return 'true' if OrdSet is an empty set, otherwise 'false'. +-spec is_empty(Ordset) -> boolean() when + Ordset :: ordset(_). + +is_empty(S) -> S=:=[]. + %% to_list(OrdSet) -> [Elem]. %% Return the elements in OrdSet as a list. |