Description:
------------
I want to split string like this: "cell:cell:cell with '\:':cell" by pattern "/(?!\\):/"

Reproduce code:
---------------
<?php
$s = "cell:cell:cell with '\\:':cell";
$s = preg_split('/(?!\\\\):/', $s);

print_r( $s );
?>

Expected result:
----------------
Array
(
    [0] => cell
    [1] => cell
    [2] => cell with ':'
    [3] => cell
)

Actual result:
--------------
Array
(
    [0] => cell
    [1] => cell
    [2] => cell with '\
    [3] => '
    [4] => cell
)