Add getter and setter in the section on basic form options

Author: mpdude

reference/forms/types/form.rst

@@ -76,6 +76,16 @@ The actual default value of this option depends on other field options:
 
 .. include:: /reference/forms/types/options/form_attr.rst.inc
 
+``getter``
+~~~~~~~~~~
+
+**type**: ``callable`` **default**: ``null``
+
+When provided, this callable will be invoked to read the value from
+the underlying object that will be used to populate the form field.
+
+More details are available in the section on :doc:`/form/data_mappers`.
+
 .. include:: /reference/forms/types/options/help.rst.inc
 
 .. include:: /reference/forms/types/options/help_attr.rst.inc
@@ -112,6 +122,16 @@ The actual default value of this option depends on other field options:
 
 .. include:: /reference/forms/types/options/required.rst.inc
 
+``setter``
+~~~~~~~~~~
+
+**type**: ``callable`` **default**: ``null``
+
+When provided, this callable will be invoked to map the form value
+back to the underlying object.
+
+More details are available in the section on :doc:`/form/data_mappers`.
+
 .. include:: /reference/forms/types/options/trim.rst.inc
 
 .. include:: /reference/forms/types/options/validation_groups.rst.inc