Completely re-reading the data transformers chapter:

1) Show an easy example using the CallbackTransformer in the beginning
2) Remove complexity related to any factories that were there before
3) Moved theoretical section to the bottom

Author: weaverryan

book/forms.rst

@@ -1141,6 +1141,8 @@ the choice is ultimately up to you.
 
         $form->get('dueDate')->setData(new \DateTime());
 
+.. _form-as-services:
+
 Defining your Forms as Services
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~