Simple PHP checksum (legacy fix)

gistfile1.txt

<?php
// Interesting legacy fix
//
// This works by replacing a collection of 10 blank spaces with a random character.
// However the \e modifier is deprecaited now, it needed replacing as it's hard to
// underststand without some notes.
//
// This line appears to come from http://php.net/manual/en/function.rand.php#86465
//
// $f->checksum = preg_replace('/([ ])/e', 'chr(rand(97,122))', '          ');

// The purpose of this line can be described as: 
// Take the first 10 characters from a string of radmonised characters from the alphabet
//
// This can be expressed in a more graceful (and supported way) as follows
$f->checksum = substr(str_shuffle(implode('', range('a', 'z'))), 0, 10);

?>