this.js

var Form = {
  [...]
  validate: function() {
    var fields = this.form.querySelectorAll('input');
    var self = this;
    fields.forEach(function(element) {
      if (self.formFields.indexOf(element.name) !== -1) {
        var allowed = self.formFields[element.name].allow;
        self.invalid[element.name] = matchValues(element, allowed);
      }

    });
    return (!nulled(this.invalid)) ? true : false;
  }
}