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<?php $currentDate = new DateTimeImmutable(); $firstOfTheMonth = new DateTimeImmutable($currentDate->format('Y-m-1')); $oneMonthInterval = new DateInterval('P1M'); var_dump($firstOfTheMonth->sub($oneMonthInterval));
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33, 8.0.0 - 8.0.12, 8.0.14 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
object(DateTimeImmutable)#4 (3) { ["date"]=> string(26) "2017-02-01 00:00:00.000000" ["timezone_type"]=> int(3) ["timezone"]=> string(16) "Europe/Amsterdam" }
Output for 7.3.32 - 7.3.33, 8.0.13
object(DateTimeImmutable)#4 (3) { ["date"]=> string(26) "2017-02-01 00:00:00.000000" ["timezone_type"]=> int(3) ["timezone"]=> string(3) "UTC" }

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