Parse error: syntax error, unexpected '        ' (T_STRING), expecting '{'

function doctype()
        {
            qa_html_theme_base::doctype();
            if(isset($this->content['a_form'])) {
                $a_form = $this->content['a_form'];
                unset($this->content['a_form']);
                $this->content['a_form'] = $a_form;
            }
        }