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<?php $var = array( 'a' => 'a', 'b' => 'b', ); array_walk($var, function ($value) { }); var_dump(key($var));
Output for 5.3.0 - 5.3.13, 5.4.0 - 5.4.3, 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 - 8.1.31, 8.2.0 - 8.2.26, 8.3.0 - 8.3.14, 8.4.1
string(1) "a"
Output for 5.3.14 - 5.3.29, 5.4.4 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.31
NULL
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/46Cbn on line 8
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/46Cbn on line 8
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/46Cbn on line 8
Process exited with code 255.
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86.82 ms | 410 KiB | 5 Q