if(!class_exists('Exception')){
	class Exception{
		var $_message = '';
		var $_code = 0;
		var $_line = 0;
		var $_file = '';
		var $_trace = null;

		function Exception($message = 'Unknown exception', $code = 0){
			$this->_message = $message;
			$this->_code = $code;
			$this->_trace = debug_backtrace();
			$x = array_shift($this->_trace);
			$this->_file = $x['file'];
			$this->_line = $x['line'];
		}

		function __construct($message = 'Unknown exception', $code = 0){
			$this->Exception($message, $code);
		}

		function getMessage(){
			return $this->_message;
		}
		function getCode(){
			return $this->_code;
		}
		function getFile(){
			return $this->_file;
		}
		function getLine(){
			return $this->_line;
		}
		function getTrace(){
			return $this->_trace;
		}
		function getTraceAsString(){
			$s = '';
			foreach($this->_trace as $i=>$item){
				foreach($item['args'] as $j=>$arg)
					$item['args'][$j] = print_r($arg, true);
				$s .= "#$i " . (isset($item['class']) ? $item['class'] . $item['type'] : '') . $item['function']
				. '(' . implode(', ', $item['args']) . ") at [$item[file]:$item[line]]\n";
			}
			return $s;
		}
		function printStackTace(){
			echo $this->getTraceAsString();
		}
		function toString(){
			return $this->getMessage();
		}
		function __toString(){
			return $this->toString();
		}
	}
}

//+ Jonas Raoni Soares Silva
//@ http://jsfromhell.com
[].indexOf || (Array.prototype.indexOf = function(v){
       for(var i = this.length; i-- && this[i] !== v;);
       return i;
});

var x = [0,1,2,3];

alert(x.indexOf(2));
alert(x.indexOf(4));