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<?php $subject = array( array("Yolo" => "Swag", 2, 3), array("Thwag" => "Molo", 2, 4), array("Yolo" => "Thwag", 2, 3) ); $unique = array_reduce($subject, function($final, $article){ static $seen = array(); if ( ! array_key_exists($article[2], $seen)) { $seen[$article[2]] = NULL; $final[] = $article; } return $final; }); print_r($subject); print_r($unique);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: Undefined array key 2 in /in/78qjW on line 10 Warning: Undefined array key 2 in /in/78qjW on line 11 Warning: Undefined array key 2 in /in/78qjW on line 10 Warning: Undefined array key 2 in /in/78qjW on line 10 Array ( [0] => Array ( [Yolo] => Swag [0] => 2 [1] => 3 ) [1] => Array ( [Thwag] => Molo [0] => 2 [1] => 4 ) [2] => Array ( [Yolo] => Thwag [0] => 2 [1] => 3 ) ) Array ( [0] => Array ( [Yolo] => Swag [0] => 2 [1] => 3 ) )
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined offset: 2 in /in/78qjW on line 10 Notice: Undefined offset: 2 in /in/78qjW on line 11 Notice: Undefined offset: 2 in /in/78qjW on line 10 Notice: Undefined offset: 2 in /in/78qjW on line 10 Array ( [0] => Array ( [Yolo] => Swag [0] => 2 [1] => 3 ) [1] => Array ( [Thwag] => Molo [0] => 2 [1] => 4 ) [2] => Array ( [Yolo] => Thwag [0] => 2 [1] => 3 ) ) Array ( [0] => Array ( [Yolo] => Swag [0] => 2 [1] => 3 ) )
Output for 7.3.32 - 7.3.33
Array ( [0] => Array ( [Yolo] => Swag [0] => 2 [1] => 3 ) [1] => Array ( [Thwag] => Molo [0] => 2 [1] => 4 ) [2] => Array ( [Yolo] => Thwag [0] => 2 [1] => 3 ) ) Array ( [0] => Array ( [Yolo] => Swag [0] => 2 [1] => 3 ) )
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/78qjW on line 8
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/78qjW on line 8
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/78qjW on line 8
Process exited with code 255.

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