[PHP-NOTES] note 130618 added to function.date

Be careful as this innocent piece of code

<?php
echo date('d.m.Y', null);
?>

outputs a different date on PHP 8 vs. earlier.

In PHP 8 `null` is treated as `null` and will make `date()` use its default value.

While on earlier PHP versions `null` will be cast to `0` therefore outputing `01.01.1970` (Unix Epoc)
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Probable Submitter: 80.221.240.179
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Manual Page -- https://php.net/manual/en/function.date.php
Edit        -- https://main.php.net/note/edit/130618
Del: integrated  -- https://main.php.net/note/delete/130618/integrated
Del: useless     -- https://main.php.net/note/delete/130618/useless
Del: bad code    -- https://main.php.net/note/delete/130618/bad+code
Del: spam        -- https://main.php.net/note/delete/130618/spam
Del: non-english -- https://main.php.net/note/delete/130618/non-english
Del: in docs     -- https://main.php.net/note/delete/130618/in+docs
Del: other reasons-- https://main.php.net/note/delete/130618
Reject      -- https://main.php.net/note/reject/130618
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