Learn closures in PHP 5.3: function() use(&$param)

function closureCreater(){
$x =1;
return function($fun=null) use(&$x){//Pass value by reference
echo "".$x++;
$fun and $fun();
};
}
$x = "hello world";
$test = closureCreater( );
$test();
$test(function(){ echo "closure test one"; });
$test(function(){ echo "closure test two"; });
$test(function( ) use($x){ echo "".$x;});

//Save the function as an array element
$x = 'outer param.';
$arr = array() ;
$arr[] = function($str)use($x){ return $str.$x; };
echo $arr[0]('test fun in arr,'); //test fun in arr ,outer param.
?>