sub new {
    my ($class, %args) = @_;
    return 'Error in syntax usage' unless _arg_validation(\%args);
    my $self = {
        ua       => _mk_ua(),
        login    => $args{login},
        password => $args{password},
        dir      => $args{dir},
        threads  => 30,
    };
    bless $self, $class;
    die 'ERROR WITH CONNECTION AUTH' unless $self->_connection_try();
    return $self;
}

##</code><code>##

my $a;

eval
{
    my $vk = mp3vk_api->new
    (
        login    => 'mail@mail.com', 
        password => 'passwd',
        dir      => 'Rhapsody',
        threads  => '10',
    );

    if (ref($vk) eq 'mp3vk_api')
    {
        my $out = $vk->search('Rhapsody');

        if (ref $out)
        {
            my $a = $vk->vk_download($out);
        }
        else
        {
            # handle possible search failure
            # throw an exception
        }
    }
    else
    {
        # handle constructor failure
        # throw an exception
    }
};

if ($@)
{
    # catch all exceptions and handle those which haven't been handled already
}
else
{
    # use $a normally
}

##</code><code>##

sub _arg_validation {
    my $args = shift;
    my $dir  = "$ENV{HOME}/vk_music/";
       $dir .= "$args->{dir}/" if defined $args->{dir};
    mkdir $dir;
    $args->{dir} = $dir;
    return 1 if defined $args->{login}                    &&
                defined $args->{password}                 &&
                        $args->{login}    =~ /^.*?\@.*?$/ &&
                        $args->{password} =~ /\w{2,}/;
    return 0;
}