--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\CssSelector\XPath\Extension;
+
+/**
+ * XPath expression translator extension interface.
+ *
+ * This component is a port of the Python cssselect library,
+ * which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
+ *
+ * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ *
+ * @internal
+ */
+interface ExtensionInterface
+{
+ /**
+ * Returns node translators.
+ *
+ * These callables will receive the node as first argument and the translator as second argument.
+ *
+ * @return callable[]
+ */
+ public function getNodeTranslators();
+
+ /**
+ * Returns combination translators.
+ *
+ * @return callable[]
+ */
+ public function getCombinationTranslators();
+
+ /**
+ * Returns function translators.
+ *
+ * @return callable[]
+ */
+ public function getFunctionTranslators();
+
+ /**
+ * Returns pseudo-class translators.
+ *
+ * @return callable[]
+ */
+ public function getPseudoClassTranslators();
+
+ /**
+ * Returns attribute operation translators.
+ *
+ * @return callable[]
+ */
+ public function getAttributeMatchingTranslators();
+
+ /**
+ * Returns extension name.
+ *
+ * @return string
+ */
+ public function getName();
+}