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<?php print json_encode([ [...['a', 'b'], ...['c', 'd']], // [a, b, c, d] array_merge(['a', 'b'], ['c', 'd']), // [a, b, c, d] ['a', 'b'] + ['c', 'd'], // [a, b] array_replace(['a', 'b'], ['c', 'd']), // [c, d] ]);
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
[["a","b","c","d"],["a","b","c","d"],["a","b"],["c","d"]]

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