- var_dump: documentation ( source)
<?php
$dob = \DateTimeImmutable::createFromString('now - 100 years')->setTime(0,0,0);
$hundredYearsAgo = \DateTimeImmutable::createFromString('now - 100 years')->setTime(0,0,0);
var_dump($dob);
var_dump($hundredYearsAgo);
var_dump($dob <= $hundredYearsAgo);