--- /dev/null
+<?php
+/**
+ * @file
+ * The interface definition for Rules to generate output.
+ */
+namespace Masterminds\HTML5\Serializer;
+
+/**
+ * To create a new rule set for writing output the RulesInterface needs to be
+ * implemented.
+ * The resulting class can be specified in the options with the
+ * key of rules.
+ *
+ * For an example implementation see \Masterminds\HTML5\Serializer\OutputRules.
+ */
+interface RulesInterface
+{
+
+ /**
+ * The class constructor.
+ *
+ * Note, before the rules can be used a traverser must be registered.
+ *
+ * @param mixed $output
+ * The output stream to write output to.
+ * @param array $options
+ * An array of options.
+ */
+ public function __construct($output, $options = array());
+
+ /**
+ * Register the traverser used in but the rules.
+ *
+ * Note, only one traverser can be used by the rules.
+ *
+ * @param \Masterminds\HTML5\Serializer\Traverser $traverser
+ * The traverser used in the rules.
+ * @return \Masterminds\HTML5\Serializer\RulesInterface $this for the current object.
+ */
+ public function setTraverser(\Masterminds\HTML5\Serializer\Traverser $traverser);
+
+ /**
+ * Write a document element (\DOMDocument).
+ *
+ * Instead of returning the result write it to the output stream ($output)
+ * that was passed into the constructor.
+ *
+ * @param \DOMDocument $dom
+ */
+ public function document($dom);
+
+ /**
+ * Write an element.
+ *
+ * Instead of returning the result write it to the output stream ($output)
+ * that was passed into the constructor.
+ *
+ * @param mixed $ele
+ */
+ public function element($ele);
+
+ /**
+ * Write a text node.
+ *
+ * Instead of returning the result write it to the output stream ($output)
+ * that was passed into the constructor.
+ *
+ * @param mixed $ele
+ */
+ public function text($ele);
+
+ /**
+ * Write a CDATA node.
+ *
+ * Instead of returning the result write it to the output stream ($output)
+ * that was passed into the constructor.
+ *
+ * @param mixed $ele
+ */
+ public function cdata($ele);
+
+ /**
+ * Write a comment node.
+ *
+ * Instead of returning the result write it to the output stream ($output)
+ * that was passed into the constructor.
+ *
+ * @param mixed $ele
+ */
+ public function comment($ele);
+
+ /**
+ * Write a processor instruction.
+ *
+ * To learn about processor instructions see \Masterminds\HTML5\InstructionProcessor
+ *
+ * Instead of returning the result write it to the output stream ($output)
+ * that was passed into the constructor.
+ *
+ * @param mixed $ele
+ */
+ public function processorInstruction($ele);
+}