--- /dev/null
+<?php
+/*
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the MIT license. For more information, see
+ * <http://www.doctrine-project.org>.
+ */
+
+namespace Doctrine\ORM\Query\AST;
+
+/**
+ * Abstract class of an AST node
+ *
+ *
+ * @link www.doctrine-project.org
+ * @since 2.0
+ * @author Guilherme Blanco <guilhermeblanco@hotmail.com>
+ * @author Jonathan Wage <jonwage@gmail.com>
+ * @author Roman Borschel <roman@code-factory.org>
+ */
+abstract class Node
+{
+ /**
+ * Double-dispatch method, supposed to dispatch back to the walker.
+ *
+ * Implementation is not mandatory for all nodes.
+ *
+ * @param $walker
+ */
+ public function dispatch($walker)
+ {
+ throw ASTException::noDispatchForNode($this);
+ }
+
+ /**
+ * Dumps the AST Node into a string representation for information purpose only
+ *
+ * @return string
+ */
+ public function __toString()
+ {
+ return $this->dump($this);
+ }
+
+ public function dump($obj)
+ {
+ static $ident = 0;
+
+ $str = '';
+
+ if ($obj instanceof Node) {
+ $str .= get_class($obj) . '(' . PHP_EOL;
+ $props = get_object_vars($obj);
+
+ foreach ($props as $name => $prop) {
+ $ident += 4;
+ $str .= str_repeat(' ', $ident) . '"' . $name . '": '
+ . $this->dump($prop) . ',' . PHP_EOL;
+ $ident -= 4;
+ }
+
+ $str .= str_repeat(' ', $ident) . ')';
+ } else if (is_array($obj)) {
+ $ident += 4;
+ $str .= 'array(';
+ $some = false;
+
+ foreach ($obj as $k => $v) {
+ $str .= PHP_EOL . str_repeat(' ', $ident) . '"'
+ . $k . '" => ' . $this->dump($v) . ',';
+ $some = true;
+ }
+
+ $ident -= 4;
+ $str .= ($some ? PHP_EOL . str_repeat(' ', $ident) : '') . ')';
+ } else if (is_object($obj)) {
+ $str .= 'instanceof(' . get_class($obj) . ')';
+ } else {
+ $str .= var_export($obj, true);
+ }
+
+ return $str;
+ }
+}