commit b4289fba8926240b2d1096b2b077cfc0876d91ed
Author: Joel Pittet <joel@pittet.ca>
Date:   Thu Mar 6 10:27:25 2014 -0800

    doc cleanup

diff --git a/core/lib/Drupal/Core/Template/TwigExtension.php b/core/lib/Drupal/Core/Template/TwigExtension.php
index c172e12..7f39f26 100644
--- a/core/lib/Drupal/Core/Template/TwigExtension.php
+++ b/core/lib/Drupal/Core/Template/TwigExtension.php
@@ -21,24 +21,24 @@ public function getFunctions() {
     // @todo re-add unset => twig_unset if this is really needed
     return array(
       // @todo Remove URL function once http://drupal.org/node/1778610 is resolved.
-      'url' => new \Twig_Function_Function('url'),
+      'url' => new \Twig_SimpleFunction('url', 'url'),
       // This function will receive a renderable array, if an array is detected.
-      'render_var' => new \Twig_Function_Function('twig_render_var'),
+      'render_var' => new \Twig_SimpleFunction('render_var', 'twig_render_var'),
     );
   }
 
   public function getFilters() {
     return array(
-      't' => new \Twig_Filter_Function('t'),
-      'trans' => new \Twig_Filter_Function('t'),
+      new \Twig_SimpleFilter('t', 't'),
+      new \Twig_SimpleFilter('trans', 't'),
       // The "raw" filter is not detectable when parsing "trans" tags. To detect
       // which prefix must be used for translation (@, !, %), we must clone the
       // "raw" filter and give it identifiable names. These filters should only
       // be used in "trans" tags.
       // @see TwigNodeTrans::compileString()
-      'passthrough' => new \Twig_Filter_Function('twig_raw_filter'),
-      'placeholder' => new \Twig_Filter_Function('twig_raw_filter'),
-      'without' => new \Twig_Filter_Function('twig_without'),
+      new \Twig_SimpleFilter('passthrough', 'twig_raw_filter'),
+      new \Twig_SimpleFilter('placeholder', 'twig_raw_filter'),
+      new \Twig_SimpleFilter('without', 'twig_without'),
     );
   }
 
diff --git a/core/lib/Drupal/Core/Template/TwigNodeVisitor.php b/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
index 75f1dce..a2cae19 100644
--- a/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
+++ b/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
@@ -10,8 +10,8 @@
 /**
  * Provides a Twig_NodeVisitor to change the generated parse-tree.
  *
- * This is used to ensure that everything printed is wrapped via the
- * twig_render_var() function in order to just write {{ content }}
+ * This is used to ensure that everything that is printed is wrapped via
+ * twig_render_var() function so that we can write for example just {{ content }}
  * in templates instead of having to write {{ render_var(content) }}.
  *
  * @see twig_render
@@ -26,7 +26,12 @@ function enterNode(\Twig_NodeInterface $node, \Twig_Environment $env) {
   }
 
   /**
-   * {@inheritdoc}
+   * Implements Twig_NodeVisitorInterface::leaveNode().
+   *
+   * We use this to inject a call to render_var -> twig_render_var()
+   * before anything is printed.
+   *
+   * @see twig_render
    */
   function leaveNode(\Twig_NodeInterface $node, \Twig_Environment $env) {
      // We use this to inject a call to render_var -> twig_render_var()
@@ -44,7 +49,7 @@ function leaveNode(\Twig_NodeInterface $node, \Twig_Environment $env) {
   }
 
   /**
-   * {@inheritdoc}
+   * Implements Twig_NodeVisitorInterface::getPriority().
    */
   function getPriority() {
     // We want to run before other NodeVisitors like Escape or Optimizer
diff --git a/core/modules/comment/templates/comment.html.twig b/core/modules/comment/templates/comment.html.twig
index c26b4b6..e8c5bb7 100644
--- a/core/modules/comment/templates/comment.html.twig
+++ b/core/modules/comment/templates/comment.html.twig
@@ -7,8 +7,8 @@
  * - author: Comment author. Can be a link or plain text.
  * - content: The content-related items for the comment display. Use
  *   {{ content }} to print them all, or print a subset such as
- *   {{ content.field_example }}. Use following code to temporarily suppress the
- *   printing of a given child element:
+ *   {{ content.field_example }}. Use the following code to temporarily suppress
+ *   the printing of a given child element:
  *   @code
  *   {{ content|without('field_example') }}
  *   @endcode
diff --git a/core/modules/system/lib/Drupal/system/Tests/Theme/TwigFilterTest.php b/core/modules/system/lib/Drupal/system/Tests/Theme/TwigFilterTest.php
index 4f58b4d..a80598c 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Theme/TwigFilterTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Theme/TwigFilterTest.php
@@ -35,9 +35,9 @@ public static function getInfo() {
   }
 
   /**
-   * Test Twig "trans" tags.
+   * Test Twig "without" filter.
    */
-  public function testTwigTransTags() {
+  public function testTwigWithoutFilter() {
     $this->drupalGet('/twig-theme-test/filter');
 
     $elements = array(
diff --git a/core/themes/bartik/templates/comment.html.twig b/core/themes/bartik/templates/comment.html.twig
index cfc56f6..f66b14b 100644
--- a/core/themes/bartik/templates/comment.html.twig
+++ b/core/themes/bartik/templates/comment.html.twig
@@ -7,8 +7,8 @@
  * - author: Comment author. Can be a link or plain text.
  * - content: The content-related items for the comment display. Use
  *   {{ content }} to print them all, or print a subset such as
- *   {{ content.field_example }}. Use following code to temporarily suppress the
- *   printing of a given child element:
+ *   {{ content.field_example }}. Use the following code to temporarily suppress
+ *   the printing of a given child element:
  *   @code
  *   {{ content|without('field_example') }}
  *   @endcode
diff --git a/core/themes/engines/twig/twig.engine b/core/themes/engines/twig/twig.engine
index 5138041..a8bb0ce 100644
--- a/core/themes/engines/twig/twig.engine
+++ b/core/themes/engines/twig/twig.engine
@@ -118,7 +118,6 @@ function twig_render_template($template_file, $variables) {
  * @see TwigNodeVisitor
  */
 function twig_render_var($arg) {
-
   // Check for numeric zero.
   if ($arg === 0) {
     return 0;
@@ -150,11 +149,16 @@ function twig_render_var($arg) {
 }
 
 /**
- * Removes child elements from a renderable array.
+ * Removes child elements from a copy of the original array.
+ *
+ * Creates a copy of the renderable array and removes child elements by key
+ * specified throught filter's arguments. The copy can be printed without these
+ * elements. The original renderable array is still available and can be used
+ * to print child elements in their entirety in the twig template.
  *
  * @param array $element
  *   The parent renderable array to exclude the child items.
- * @param string[] $args,...
+ * @param string[] $args, ...
  *   The string keys of $element to prevent printing.
  *
  * @return array