3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo = [ 0 => [ 'bar' => 'baz', 'qux' => [ 'x', 'y', 'y', ], ], ]; echo json_encode($foo, JSON_FORCE_OBJECT | JSON_PRETTY_PRINT), PHP_EOL, json_encode((object) $foo, JSON_PRETTY_PRINT);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
{ "0": { "bar": "baz", "qux": { "0": "x", "1": "y", "2": "y" } } } { "0": { "bar": "baz", "qux": [ "x", "y", "y" ] } }

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