- var_dump: documentation ( source)
- class_exists: documentation ( source)
<?php
use \This\Namespase\Does\Not\Exists\FooBar;
var_dump(
FooBar::class, // use ::class
\class_exists(FooBar::class), // check class existence with autoload
\class_exists(FooBar::class, false) // check class existence without autoload
);