diff --git a/core/lib/Drupal/Core/Template/Attribute.php b/core/lib/Drupal/Core/Template/Attribute.php
index 076cfd3..ac94cab 100644
--- a/core/lib/Drupal/Core/Template/Attribute.php
+++ b/core/lib/Drupal/Core/Template/Attribute.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\Template;
 
-
 /**
  * A class that can be used for collecting then rendering HTML attributtes.
  *
@@ -17,7 +16,7 @@
  *  $attributes = new Attribute(array('id' => 'socks'));
  *  $attributes['class'] = array('black-cat', 'white-cat');
  *  $attributes['class'][] = 'black-white-cat';
- *  echo '<cat ' . $attributes . '>';
+ *  echo '<cat' . $attributes . '>';
  *  // Produces <cat id="socks" class="black-cat white-cat black-white-cat">
  * @endcode
  *
@@ -26,7 +25,7 @@
  *  $attributes = new Attribute(array('id' => 'socks'));
  *  $attributes['class'] = array('black-cat', 'white-cat');
  *  $attributes['class'][] = 'black-white-cat';
- *  echo '<cat class="cat ' . $attributes['class'] . '" ' . $attributes . '>';
+ *  echo '<cat class="cat ' . $attributes['class'] . '"' . $attributes . '>';
  *  // Produces <cat class="cat black-cat white-cat black-white-cat" id="socks">
  * @endcode
  */
@@ -64,6 +63,20 @@ public function offsetGet($name) {
    * Implements ArrayAccess::offsetSet().
    */
   public function offsetSet($name, $value) {
+    $value = $this->createAttributeValue($name, $value);
+    $this->storage[$name] = $value;
+  }
+
+/**
+ * Creates the different types of attribute values.
+ * @param string $name
+ *   @todo
+ * @param mixed $value
+ *   @todo
+ * @return object
+ *
+ */
+  protected function createAttributeValue($name, $value) {
     if (is_array($value)) {
       $value = new AttributeArray($name, $value);
     }
@@ -73,13 +86,7 @@ public function offsetSet($name, $value) {
     elseif (!is_object($value)) {
       $value = new AttributeString($name, $value);
     }
-    // The $name could be NULL.
-    if (isset($name)) {
-      $this->storage[$name] = $value;
-    }
-    else {
-      $this->storage[] = $value;
-    }
+    return $value;
   }
 
   /**
@@ -105,7 +112,7 @@ public function __toString() {
       if (!$value->printed()) {
         $rendered = is_object($value) ? $value->render() : (check_plain($name) . ' = "' . check_plain($value) . '"');
         if ($rendered) {
-          $return .= " $rendered";
+          $return .= ' ' . $rendered;
         }
       }
     }
@@ -129,12 +136,4 @@ public function  __clone() {
   public function getIterator() {
     return new \ArrayIterator($this->storage);
   }
-
-  /**
-   * Returns the whole array.
-   */
-  public function value() {
-    return $this->value;
-  }
-
 }
diff --git a/core/lib/Drupal/Core/Template/AttributeArray.php b/core/lib/Drupal/Core/Template/AttributeArray.php
index d3521e0..a4d1d12 100644
--- a/core/lib/Drupal/Core/Template/AttributeArray.php
+++ b/core/lib/Drupal/Core/Template/AttributeArray.php
@@ -14,13 +14,13 @@
  * To use with Attribute, the array must be specified.
  * Correct:
  * @code
- *  $attributes = new Attribute(array());
+ *  $attributes = new Attribute();
  *  $attributes['class'] = array();
  *  $attributes['class'][] = 'cat';
  * @endcode
  * Incorrect:
  * @code
- *  $attributes = new Attribute(array());
+ *  $attributes = new Attribute();
  *  $attributes['class'][] = 'cat';
  * @endcode
  *
@@ -66,7 +66,7 @@ public function offsetExists($offset) {
    */
   public function __toString() {
     $this->printed = TRUE;
-    return implode(' ', array_map('check_plain', $this->value));
+    return check_plain(implode(' ', $this->value));
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Template/AttributeBoolean.php b/core/lib/Drupal/Core/Template/AttributeBoolean.php
index 48ca388..7bfc527 100644
--- a/core/lib/Drupal/Core/Template/AttributeBoolean.php
+++ b/core/lib/Drupal/Core/Template/AttributeBoolean.php
@@ -16,12 +16,12 @@
  *
  * To set a boolean attribute on the Attribute class, set it to TRUE.
  * @code
- *  $attributes = new Attribute(array());
+ *  $attributes = new Attribute();
  *  $attributes['disabled'] = TRUE;
- *  echo '<select ' . $attributes . '/>';
+ *  echo '<select' . $attributes . '/>';
  *  // produces <select disabled>;
  *  $attributes['disabled'] = FALSE;
- *  echo '<select ' . $attributes . '/>';
+ *  echo '<select' . $attributes . '/>';
  *  // produces <select>;
  * @endcode
  *
diff --git a/core/modules/rdf/rdf.module b/core/modules/rdf/rdf.module
index aaea6bb..f63a19a 100644
--- a/core/modules/rdf/rdf.module
+++ b/core/modules/rdf/rdf.module
@@ -483,12 +483,15 @@ function rdf_preprocess_html(&$variables) {
   // Adds RDF namespace prefix bindings in the form of an RDFa 1.1 prefix
   // attribute inside the html element.
   $prefixes = array();
+  // debug($variables['html_attributes']['prefix']);
   if (!isset($variables['html_attributes']['prefix'])) {
     $variables['html_attributes']['prefix'] = array();
   }
   foreach(rdf_get_namespaces() as $prefix => $uri) {
+    // debug($prefix);
     $variables['html_attributes']['prefix'][] = $prefix . ': ' . $uri . "\n";
   }
+  // debug($variables['html_attributes']['prefix']);
 }
 
 /**
diff --git a/core/modules/system/lib/Drupal/system/Tests/Common/AttributesUnitTest.php b/core/modules/system/lib/Drupal/system/Tests/Common/AttributesUnitTest.php
index 7b5305d..c561529 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Common/AttributesUnitTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Common/AttributesUnitTest.php
@@ -37,6 +37,10 @@ function testDrupalAttributes() {
     $this->assertIdentical((string) new Attribute(array('alt' => '')), ' alt=""', 'Empty attribute value #1.');
     $this->assertIdentical((string) new Attribute(array('alt' => NULL)), ' alt=""', 'Empty attribute value #2.');
 
+    // Verify boolean attribute values are rendered correctly.
+    $this->assertIdentical((string) new Attribute(array('disabled' => TRUE)), ' disabled', 'Boolean attribute is rendered.');
+    $this->assertIdentical((string) new Attribute(array('disabled' => FALSE)), '', 'Boolean attribute is not rendered.');
+
     // Verify multiple attributes are rendered.
     $attributes = array(
       'id' => 'id-test',