Support previous exceptions in PHP < 5.3.0.

Taken from http://framework.zend.com/wiki/display/ZFPROP/previous+Exception+on+Zend_Exception+-+Marc+Bennewitz

diff --git a/framework/Exception/lib/Horde/Exception.php b/framework/Exception/lib/Horde/Exception.php
index 2c2553d..2ce6375 100644 (file)
--- a/framework/Exception/lib/Horde/Exception.php
+++ b/framework/Exception/lib/Horde/Exception.php
@@ -1,15 +1,75 @@
 <?php
-/**
- * Horde base exception class.
- *
- * Copyright 2008-2010 The Horde Project (http://www.horde.org/)
- *
- * See the enclosed file COPYING for license information (LGPL). If you
- * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html.
- *
- * @category Horde
- * @package  Horde_Exception
- */
-class Horde_Exception extends Exception
-{
-}
+if (version_compare(PHP_VERSION, '5.3.0', '<')) {
+    /**
+     * Horde base exception class that supports prior exception for PHP < 5.3.0
+     *
+     * Originates from
+     * http://framework.zend.com/wiki/display/ZFPROP/previous+Exception+on+Zend_Exception+-+Marc+Bennewitz
+     *
+     * Copyright 2008-2010 The Horde Project (http://www.horde.org/)
+     *
+     * See the enclosed file COPYING for license information (LGPL). If you
+     * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html.
+     *
+     * @category Horde
+     * @package  Horde_Exception
+     */
+    class Horde_Exception extends Exception
+    {
+
+        private $_previous = null;
+
+        /**
+         * Construct the exception
+         *
+         * @param string $msg
+         * @param int $code
+         * @param Exception $previous
+         */
+        public function __construct($msg = '', $code = 0, Exception $previous = null)
+        {
+            parent::__construct($msg, $code);
+            $this->_previous = $previous;
+        }
+
+        /**
+         * Returns previous Exception
+         *
+         * @return Exception|null
+         */
+        final public function getPrevious()
+        {
+            return $this->_previous;
+        }
+
+        /**
+         * String representation of the exception
+         *
+         * @return string
+         */
+        public function __toString()
+        {
+            if ($this->getPrevious()) {
+                return $this->getPrevious()->__toString() . "\n\nNext " . parent::__toString();
+            } else {
+                return parent::__toString();
+            }
+        }
+
+    }
+} else {
+    /**
+     * Horde base exception class.
+     *
+     * Copyright 2008-2010 The Horde Project (http://www.horde.org/)
+     *
+     * See the enclosed file COPYING for license information (LGPL). If you
+     * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html.
+     *
+     * @category Horde
+     * @package  Horde_Exception
+     */
+    class Horde_Exception extends Exception
+    {
+    }
+}
\ No newline at end of file