Mootools way to retrieve forms values

ConvertForm.js

/**
 * Retrieve form values as an object
 *
 * Inspired by Element.toQueryString
 * @see Dimitar Christoff response on http://stackoverflow.com/questions/2166042/how-to-convert-form-data-to-object-using-mootools
 *
 * @return object form
 *
 * @author Ludovic Vigouroux <ludovicv@theodo.fr> with the help of Fabrice Bernhard
 * @since  2012-02-29
 */
Element.implement({
  toJSON: function(){
    var json = {};
    this.getElements('input, select, textarea').each(function(el){
      var type = el.type;
      if (!el.name || el.disabled || type == 'submit' || type == 'reset' || type == 'file' || type == 'image') return;

      var value = (el.get('tag') == 'select') ? el.getSelected().map(function(opt){
        // IE
        return document.id(opt).get('value');
      }) : ((type == 'radio' || type == 'checkbox') && !el.checked) ? null : el.get('value');

      Array.from(value).each(function(val){
        // retrieve form
        var reg = /[\W]+/g;
        var form_names = el.name.split(reg);
        form_names.pop(); // I dont find out why regex add an empty value
        var form_graph = {};
        var key = form_names.pop();
        form_graph[key] = val;
        var form = (function createArray(form_names) {
          if (0 == form_names.length) {
            return form_graph;
          } else {
            var key = form_names.pop();
            old_form_graph = Object.clone(form_graph);
            form_graph = {}
            form_graph[key] = old_form_graph;
            return createArray(form_names);
          }
        })(form_names);

        Object.merge(json, form);
      });
    });

    return json;
  }
});