%% %CopyrightBegin%
%%
%% SPDX-License-Identifier: Apache-2.0
%%
%% Copyright Ericsson AB 2021-2025. All Rights Reserved.
%%
%% %CopyrightEnd%

[;1m  union(SetOfSets)[0m

  Returns the union of the set of sets [;;4mSetOfSets[0m.

[;1mExamples[0m

    1> S1 = sofs:set([a,b,c]).
    2> S2 = sofs:set([b,1,2]).
    3> S3 = sofs:set([a,d,e])
    4> S4 = sofs:from_sets([S1,S2,S3]).
    5> S5 = sofs:union(S4).
    6> sofs:to_external(S5).
    [1,2,a,b,c,d,e]
