Add IDAccumulator.

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@129 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/IDAccumulator.php

@@ -0,0 +1,27 @@
+<?php
+
+class HTMLPurifier_IDAccumulator
+{
+    
+    var $ids = array();
+    
+    function &instance() {
+        static $instance = null;
+        if (empty($instance)) {
+            $instance = new HTMLPurifier_IDAccumulator();
+        }
+        return $instance;
+    }
+    
+    function add($id) {
+        if (isset($this->ids[$id])) return false;
+        return $this->ids[$id] = true;
+    }
+    
+    function reset() {
+        $this->ids = array();
+    }
+    
+}
+
+?>