sub AddToUserArray {
    my ($UserID) = @_; # Like this because it scales well for many params

    # return 1 to skip addtouserlog ()

    # return if bad UserID
    return 1 if $UserID eq "";

    # return if handled user already
    return 1 if grep {$_ eq $UserID} @Participants;

    push @Participants, $UserID;
    return; # Generally better to return undef than 0
}