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<?php $arr = [0 => 23, 1 => 1, 2 => 22]; var_dump($arr); asort($arr); var_dump($arr); $key = array_shift(array_keys($arr)); var_dump($key);
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(3) { [0]=> int(23) [1]=> int(1) [2]=> int(22) } array(3) { [1]=> int(1) [2]=> int(22) [0]=> int(23) } Notice: Only variables should be passed by reference in /in/sSgCv on line 6 int(1)
Output for 7.3.32 - 7.3.33
array(3) { [0]=> int(23) [1]=> int(1) [2]=> int(22) } array(3) { [1]=> int(1) [2]=> int(22) [0]=> int(23) } int(1)
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
array(3) { [0]=> int(23) [1]=> int(1) [2]=> int(22) } array(3) { [1]=> int(1) [2]=> int(22) [0]=> int(23) } Strict Standards: Only variables should be passed by reference in /in/sSgCv on line 6 int(1)
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/sSgCv on line 2
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 '[' in /in/sSgCv on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/sSgCv on line 2
Process exited with code 255.

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