Online PHP editor | output for iZEks

@ 2016-02-07T10:17:56Z

<?php

class Foo extends DateTime {
    const ATOM = 'Y-m-d';
}
echo (new DateTime('2015-02-01'))->format(DateTime::ATOM), PHP_EOL;
echo (new Foo('2015-02-01'))->format(Foo::ATOM);

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