ResourceBundle返回NULL，不会引发任何错误

\\ResourceBundle

$bundle   = \'/var/www/libs/icudt48l.dat\';
$resource = new \\ResourceBundle(\'en_US\', $bundle, true);
var_dump($resource, is_file($bundle)); //--> NULL, TRUE

<?php
$b = \'/var/www/libs/icudt48l\';
$r = new \\ResourceBundle(\'en_US\', $b, true);
var_dump($r instanceof \\ResourceBundle); //-> TRUE

$resource = resourcebundle_create(\'en_US\',$bundle,true);