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<?php $array1 = [0 => 'one', 1 => 'two']; $array2 = [1 => 'two', 0 => 'one']; var_dump(json_encode($array1)); var_dump(json_encode($array2));
Output for 8.0.1 - 8.0.30, 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
string(13) "["one","two"]" string(21) "{"1":"two","0":"one"}"

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