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<?php $var = [ 'a' => 'a', 'b' => 'b', ]; foreach ($var as $value) { } var_dump(key($var));
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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
string(1) "a"
Output for 5.5.0 - 5.5.36, 5.6.0 - 5.6.28
NULL

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177.59 ms | 401 KiB | 228 Q