sub new {
     
    trace() if $ENV{TRACE};
 
    my $self = {};
    bless $self, shift;
 
    $self->{engines} = $self->_dt;
 
    return $self;
}
sub _dt {
     
    trace() if $ENV{TRACE};
 
    my $self = shift;
 
    my $dt = {
        all => \&all,
        has => \&has,
        missing => \&missing,
        lines => \&lines,
        objects => \&objects,
        search_replace => \&search_replace,
        inject_after => \&inject_after,
        dt_test => \&dt_test,
        _test => \&_test,
        _test_bad => \&_test_bad,
    };
 
    return $dt;
}