Recreating create_function for PHP 7.2

gistfile1.php

<?php

// WARNING - You should always ensure that the code cannot be updated
//           using an anonymous function before using this

function createCallback($paramList, $code) {
  $callback = create_function($paramList, $code);
  return $callback;
}

function createCallbackPHP72($paramList, $code) {
  $callback = "create_function_" . uniqid() . mt_rand();
  eval("function $callback($paramList) { $code }");
  return $callback;
}

$cb1 = createCallback('$a,$b', 'echo $a; echo $b;');
$cb2 = createCallbackPHP72('$a,$b', 'echo $a; echo $b;');

$cb1(1, 2);
$cb2(3, 4);