Update best_practices/templates.rst

Author: GuilhemN

best_practices/templates.rst

@@ -60,8 +60,8 @@ Twig Extensions
 
 .. best-practice::
 
-    Define your Twig extensions in the ``AppBundle/Twig/`` directory and
-    configure them using the ``app/config/services.yml`` file.
+    Define your Twig extensions in the ``AppBundle/Twig/`` directory. Your
+    application will automatically detect them and configure them.
 
 Our application needs a custom ``md2html`` Twig filter so that we can transform
 the Markdown contents of each post into HTML.
@@ -97,8 +97,8 @@ Markdown content into HTML::
     }
 
 Next, create a new Twig extension and define a new filter called ``md2html``
-using the ``Twig_SimpleFilter`` class. Inject the newly defined ``markdown``
-service in the constructor of the Twig extension:
+using the ``Twig_SimpleFilter`` class. Inject the newly defined ``Markdown``
+class in the constructor of the Twig extension:
 
 .. code-block:: php
 
@@ -137,21 +137,11 @@ service in the constructor of the Twig extension:
         }
     }
 
-Lastly make sure these new classes are registered as services:
+And that's it!
 
-.. code-block:: yaml
-
-    # app/config/services.yml
-    services:
-        _defaults:
-            # ... be sure autowiring and autoconfiguring are enabled
-            autowire: true
-            autoconfigure: true
-        # ...
-
-        # add Service/ to the list of directories to load services from
-        AppBundle\:
-            resource: '../../src/AppBundle/{Service,Command,Form,EventSubscriber,Twig,Security}'
+Your application will :ref:`autoconfigure <services-autoconfigure>` your twig
+extension and inject a ``Markdown`` instance in it thanks to
+:doc:`autowiring </service_container/autowiring>`.
 
 .. _`Twig`: http://twig.sensiolabs.org/
 .. _`Parsedown`: http://parsedown.org/