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<?php $l=[]; $l[]=1; $l[]=2; $l[]=3; var_dump($l);
Output for 5.6.38, 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(3) { [0]=> int(1) [1]=> int(2) [2]=> int(3) }

preferences:
150.04 ms | 403 KiB | 204 Q