- var_dump: documentation ( source)
- is_a: documentation ( source)
- is_subclass_of: documentation ( source)
<?php
class A {} class B extends A {}
var_dump(is_a('A','B'));
var_dump(is_a('B','A'));
var_dump(is_subclass_of('A','B'));
var_dump(is_subclass_of('B','A'));
var_dump(is_subclass_of('A','A'));