README.md

 require('classes/core/core.php');

 $data = array(
     'err' => 'ok',
     'data' => array(
	     array(
		     'key1' => 1,
		     'key2' => 'abc',
		     'key3' => array(1,2,3)
	     ),
	     array(
		     'key1' => 2,
		     'key2' => 'def',
		     'key3' => array(1,2,3)
	     ),
	     array(
		     'key1' => 3,
		     'key2' => '1aab',
		     'key3' => array(1,2,3)
	     ),
     ),
 );

 W($data)->query('#data key1')->each(function($a){
     return $a = $a + 1;
 });
 W($data)->query('#data key2')->each(function($a){
     return $a = strtoupper($a);
 });
 W($data)->query('#data key3')->each(function($a){
     array_push($a, 4);
     return $a;
 });

 print_r($data);