original_string: public function subscriber_selection_form(user_selector_base $existinguc, user_selector_base $potentialuc) {
          $output = '';
          $formattributes = array();
          $formattributes['id'] = 'subscriberform';
          $formattributes['action'] = '';
          $formattributes['method'] = 'post';
          $output .= html_writer::start_tag('form', $formattributes);
          $output .= html_writer::empty_tag('input', array('type'=>'hidden', 'name'=>'sesskey', 'value'=>sesskey()));
  
          $existingcell = new html_table_cell();
          $existingcell->text = $existinguc->display(true);
          $existingcell->attributes['class'] = 'existing';
          $actioncell = new html_table_cell();
          $actioncell->text  = html_writer::start_tag('div', array());
          $actioncell->text .= html_writer::empty_tag('input', array('type'=>'submit', 'name'=>'subscribe', 'value'=>$this->page->theme->larrow.' '.get_string('add'), 'class'=>'actionbutton'));
          $actioncell->text .= html_writer::empty_tag('br', array());
          $actioncell->text .= html_writer::empty_tag('input', array('type'=>'submit', 'name'=>'unsubscribe', 'value'=>$this->page->theme->rarrow.' '.get_string('remove'), 'class'=>'actionbutton'));
          $actioncell->text .= html_writer::end_tag('div', array());
          $actioncell->attributes['class'] = 'actions';
          $potentialcell = new html_table_cell();
          $potentialcell->text = $potentialuc->display(true);
          $potentialcell->attributes['class'] = 'potential';
  
          $table = new html_table();
          $table->attributes['class'] = 'subscribertable boxaligncenter';
          $table->data = array(new html_table_row(array($existingcell, $actioncell, $potentialcell)));
          $output .= html_writer::table($table);
  
          $output .= html_writer::end_tag('form');
          return $output;
      }
code: public function subscriber_selection_form(user_selector_base $existinguc, user_selector_base $potentialuc) {
          $output = '';
          $formattributes = array();
          $formattributes['id'] = 'subscriberform';
          $formattributes['action'] = '';
          $formattributes['method'] = 'post';
          $output .= html_writer::start_tag('form', $formattributes);
          $output .= html_writer::empty_tag('input', array('type'=>'hidden', 'name'=>'sesskey', 'value'=>sesskey()));
  
          $existingcell = new html_table_cell();
          $existingcell->text = $existinguc->display(true);
          $existingcell->attributes['class'] = 'existing';
          $actioncell = new html_table_cell();
          $actioncell->text  = html_writer::start_tag('div', array());
          $actioncell->text .= html_writer::empty_tag('input', array('type'=>'submit', 'name'=>'subscribe', 'value'=>$this->page->theme->larrow.' '.get_string('add'), 'class'=>'actionbutton'));
          $actioncell->text .= html_writer::empty_tag('br', array());
          $actioncell->text .= html_writer::empty_tag('input', array('type'=>'submit', 'name'=>'unsubscribe', 'value'=>$this->page->theme->rarrow.' '.get_string('remove'), 'class'=>'actionbutton'));
          $actioncell->text .= html_writer::end_tag('div', array());
          $actioncell->attributes['class'] = 'actions';
          $potentialcell = new html_table_cell();
          $potentialcell->text = $potentialuc->display(true);
          $potentialcell->attributes['class'] = 'potential';
  
          $table = new html_table();
          $table->attributes['class'] = 'subscribertable boxaligncenter';
          $table->data = array(new html_table_row(array($existingcell, $actioncell, $potentialcell)));
          $output .= html_writer::table($table);
  
          $output .= html_writer::end_tag('form');
          return $output;
      }
code_tokens: public function subscriber_selection_form ( user_selector_base $ existinguc , user_selector_base $ potentialuc ) { $ output = '' ; $ formattributes = array ( ) ; $ formattributes [ 'id' ] = 'subscriberform' ; $ formattributes [ 'action' ] = '' ; $ formattributes [ 'method' ] = 'post' ; $ output .= html_writer :: start_tag ( 'form' , $ formattributes ) ; $ output .= html_writer :: empty_tag ( 'input' , array ( 'type' => 'hidden' , 'name' => 'sesskey' , 'value' => sesskey ( ) ) ) ; $ existingcell = new html_table_cell ( ) ; $ existingcell -> text = $ existinguc -> display ( true ) ; $ existingcell -> attributes [ 'class' ] = 'existing' ; $ actioncell = new html_table_cell ( ) ; $ actioncell -> text = html_writer :: start_tag ( 'div' , array ( ) ) ; $ actioncell -> text .= html_writer :: empty_tag ( 'input' , array ( 'type' => 'submit' , 'name' => 'subscribe' , 'value' => $ this -> page -> theme -> larrow . ' ' . get_string ( 'add' ) , 'class' => 'actionbutton' ) ) ; $ actioncell -> text .= html_writer :: empty_tag ( 'br' , array ( ) ) ; $ actioncell -> text .= html_writer :: empty_tag ( 'input' , array ( 'type' => 'submit' , 'name' => 'unsubscribe' , 'value' => $ this -> page -> theme -> rarrow . ' ' . get_string ( 'remove' ) , 'class' => 'actionbutton' ) ) ; $ actioncell -> text .= html_writer :: end_tag ( 'div' , array ( ) ) ; $ actioncell -> attributes [ 'class' ] = 'actions' ; $ potentialcell = new html_table_cell ( ) ; $ potentialcell -> text = $ potentialuc -> display ( true ) ; $ potentialcell -> attributes [ 'class' ] = 'potential' ; $ table = new html_table ( ) ; $ table -> attributes [ 'class' ] = 'subscribertable boxaligncenter' ; $ table -> data = array ( new html_table_row ( array ( $ existingcell , $ actioncell , $ potentialcell ) ) ) ; $ output .= html_writer :: table ( $ table ) ; $ output .= html_writer :: end_tag ( 'form' ) ; return $ output ; }
docstring: This method is used to generate HTML for a subscriber selection form that
  uses two user_selector controls
  
  @param user_selector_base $existinguc
  @param user_selector_base $potentialuc
  @return string
docstring_tokens: This method is used to generate HTML for a subscriber selection form that uses two user_selector controls