Form Validation Errors Not Showing?

[eluser]seegan[/eluser]
// Just code like this..

Code:

public function test()
    {
     $this->load->library('form_validation');
        $this->form_validation->set_rules('tin_number','TIN Number','required');

        if($this->form_validation->run() == TRUE)
        {
            echo $this->input->post('tin_number');
        }
       else {
        echo validation_errors();
        echo form_open();
        echo form_input('tin_number',set_value('tin_number'));
        echo form_submit('submit','Submit');
        echo form_close();
       }
    }

//You need to load 'form_validation' library