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<?php $data = ['A','A','A','B','A','B']; $data = array_filter( $data, function($value) { static $previous = null; $return = $value != $previous; $previous = $value; return $return; } ); var_dump($data);
Output for 5.5.0 - 5.5.38, 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 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
array(4) { [0]=> string(1) "A" [3]=> string(1) "B" [4]=> string(1) "A" [5]=> string(1) "B" }
preferences:
178.01 ms | 404 KiB | 332 Q