echo '

';
$arrayRaw = array('2' => 'c','3' => 'd', '4' => 'e', '5' => 'f');
echo "0", PHP_EOL;
print_r(array_splice($arrayRaw, 2));
echo "1", PHP_EOL;
print_r($arrayRaw);

$arrayRaw = array('2' => 'c','3' => 'd', '4' => 'e', '5' => 'f');
array_slice($arrayRaw, 0, 2, true);
echo "2", PHP_EOL;
print_r(array_slice($arrayRaw, 0, 2, true));
echo "3", PHP_EOL;
print_r($arrayRaw);
echo '

0
Array
(
    [0] => e
    [1] => f
)
1
Array
(
    [0] => c
    [1] => d
)
2
Array
(
    [2] => c
    [3] => d
)
3
Array
(
    [2] => c
    [3] => d
    [4] => e
    [5] => f
)