The true default value of this option depends on the field options:

* If ``data_class`` is set and ``required`` is ``true``, then ``null``;

* If ``data_class`` is set and ``required`` is ``false``, then ``new $data_class()``;

* If ``data_class`` is set and ``required`` is ``true``, then ``new $data_class()``;

* If ``data_class`` is set and ``required`` is ``false``, then ``null``;

* If ``data_class`` is not set and ``compound`` is ``true``, then ``array()``;

* If ``data_class`` is not set and ``compound`` is ``false``, then ``null``.

.. note::

The required optiondoesalsoaffect the wayhow empty dataof your form is

beinghandled. Forfurther details check the `empty_data`_ option.

The required option alsoaffectshow empty datafor each field is

handled. Formore details, see the `empty_data`_ option.

.. _`HTML5 required attribute`:http://diveintohtml5.info/forms.html