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<?php echo json_encode([]); echo PHP_EOL; echo json_encode( [ 12 => [ 'a' => 1, 'b' => 2 ], 13 => [ 'c'=>4, 'd'=>'e' ] ] ); echo PHP_EOL . '----' . PHP_EOL;; echo json_encode([], JSON_FORCE_OBJECT); echo PHP_EOL; echo json_encode( [ 12 => [ 'a' => 1, 'b' => 2 ], 13 => [ 'c'=>4, 'd'=>'e' ] ], JSON_FORCE_OBJECT );
Output for 8.0.28, 8.1.23 - 8.1.27, 8.2.6 - 8.2.17, 8.3.0 - 8.3.4
[] {"12":{"a":1,"b":2},"13":{"c":4,"d":"e"}} ---- {} {"12":{"a":1,"b":2},"13":{"c":4,"d":"e"}}

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62.54 ms | 402 KiB | 25 Q