Online PHP editor | output for u5Rv8

<?php function dumpMappedRow($mappedRow) { var_dump([ 'created' => $mappedRow['created']->format(DateTime::ISO8601), 'modified' => $mappedRow['modified']->format(DateTime::ISO8601) ]); } function mutableDemo() { $date = DateTime::createFromFormat("Ymd", "2015-11-24"); $mappedRow['created'] = $date; $mappedRow['modified'] = $date; dumpMappedRow($mappedRow); $mappedRow['modified']->setDate("2015", "11", "15"); dumpMappedRow($mappedRow); if ($mappedRow['created']->getTimestamp() === $mappedRow['modified']->getTimestamp()) { echo "\nCreated and Modified are set to the same value."; } } function immutableDemo() { $date = DateTimeImmutable::createFromFormat("Ymd", "2015-11-24"); $mappedRow['created'] = $date; $mappedRow['modified'] = $date; dumpMappedRow($mappedRow); $mappedRow['modified']->setDate("2015", "11", "15"); dumpMappedRow($mappedRow); if ($mappedRow['created']->getTimestamp() === $mappedRow['modified']->getTimestamp()) { echo "\nCreated and Modified are set to the same value."; } } objectDemo(); echo "\n\n==========\n\n"; stringDemo();