add note about parameters in imports

book/service_container.rst

@@ -418,6 +418,8 @@ configuration.
         // app/config/config.php
         $loader->import('@AcmeHelloBundle/Resources/config/services.php');
 
+.. include:: /components/dependency_injection/_imports-parameters-note.rst.inc
+
 The ``imports`` directive allows your application to include service container
 configuration resources from any other location (most commonly from bundles).
 The ``resource`` location, for files, is the absolute path to the resource

components/dependency_injection/_imports-parameters-note.rst.inc

@@ -0,0 +1,31 @@
+.. note::
+
+    Due to the way in which parameters are resolved, you cannot use them to
+    build paths in imports dynamically. This means that something like the
+    following doesn't work:
+
+    .. configuration-block::
+
+        .. code-block:: yaml
+
+            # app/config/config.yml
+            imports:
+                - { resource: "%kernel.root_dir%/parameters.yml" }
+
+        .. code-block:: xml
+
+            <!-- app/config/config.xml -->
+            <?xml version="1.0" encoding="UTF-8" ?>
+            <container xmlns="http://symfony.com/schema/dic/services"
+                xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+                xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
+
+                <imports>
+                    <import resource="%kernel.root_dir%/parameters.yml" />
+                </imports>
+            </container>
+
+        .. code-block:: php
+
+            // app/config/config.php
+            $loader->import('%kernel.root_dir%/parameters.yml');

cookbook/configuration/configuration_organization.rst

@@ -148,6 +148,8 @@ needed for the ``app/config/dev/config.yml`` file:
 
         // ...
 
+.. include:: /components/dependency_injection/_imports-parameters-note.rst.inc
+
 Semantic Configuration Files
 ----------------------------
 

cookbook/configuration/environments.rst

@@ -262,6 +262,8 @@ The best way to accomplish this is via a new environment called, for example,
             'profiler' => array('only-exceptions' => false),
         ));
 
+.. include:: /components/dependency_injection/_imports-parameters-note.rst.inc
+
 And with this simple addition, the application now supports a new environment
 called ``benchmark``.