Adding JS to region other then header or footer

It is said here in docs api you can add JS file to some other region then header of footer…
To to that you need to assign it to that region but also add it in html/page preprocess

function my_module_preprocess_page(&$variables) {
    drupal_add_js(drupal_get_path('module', 'my_module') . '/includes/some.js', array(
      'type' => 'file',
      'scope' => 'region_scripts',
      'weight' => 50,

 $variables['scripts'] = drupal_get_js();
* Implements hook_process_html().
function my_module_process_html(&$vars) {
$vars['region_scripts'] = drupal_get_js('region_scripts');

This above can also be done in theme, both on page and html layer (process and preprocess)