title: How to pass additional parameter to wordpress filter?
body: <pre><code>add_filter('wp_list_pages_excludes', 'gr_wp_list_pages_excludes');
  
  function gr_wp_list_pages_excludes($exclude_array) {    
      $id_array=$array('22');
      $exclude_array=array_merge($id_array, $exclude_array);
      return $exclude_array;
  }
  </code></pre>
  
  <p>I'm a newbie to wordpress. The above code works fine. But I need to pass additional argument, say $mu_cust_arg to the function gr_wp_list_pages_excludes. How can I make use of it via apply_filters, or any other methods?
  Any help is appreciated.</p>
  
  <p>Thanks in advance.</p>