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<?php class A { public static $insert = []; } $data = ['a', 'b', 'c']; array_filter($data, function (string $d) { if ($d === 'a') { return true; } A::$insert[] = $d; return false; }); var_dump(A::$insert);
Output for 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array(2) { [0]=> string(1) "b" [1]=> string(1) "c" }

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