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<?php $array = array( 'filters'=> array('where'=>array('yr'=>1994))); $keys = array_keys($array['filters']['where']); echo array_shift(var_dump(array_keys($array['filters']['where'])));
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(1) { [0]=> string(2) "yr" } Notice: Only variables should be passed by reference in /in/tLLeK on line 4 Fatal error: Uncaught TypeError: array_shift(): Argument #1 ($array) must be of type array, null given in /in/tLLeK:4 Stack trace: #0 /in/tLLeK(4): array_shift(NULL) #1 {main} thrown in /in/tLLeK on line 4
Process exited with code 255.
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
array(1) { [0]=> string(2) "yr" } Notice: Only variables should be passed by reference in /in/tLLeK on line 4 Warning: array_shift() expects parameter 1 to be array, null given in /in/tLLeK on line 4
Output for 7.3.32 - 7.3.33
array(1) { [0]=> string(2) "yr" } Warning: array_shift() expects parameter 1 to be array, null given in /in/tLLeK on line 4
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
array(1) { [0]=> string(2) "yr" } Strict Standards: Only variables should be passed by reference in /in/tLLeK on line 4 Warning: array_shift() expects parameter 1 to be array, null given in /in/tLLeK on line 4
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
array(1) { [0]=> string(2) "yr" } Strict Standards: Only variables should be passed by reference in /in/tLLeK on line 4 Warning: array_shift(): The argument should be an array in /in/tLLeK on line 4
Output for 5.0.5
array(1) { [0]=> string(2) "yr" } Fatal error: Only variables can be passed by reference in /in/tLLeK on line 4
Process exited with code 255.
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.4
array(1) { [0]=> string(2) "yr" } Warning: array_shift(): The argument should be an array in /in/tLLeK on line 4
Output for 4.3.0 - 4.3.1
array(1) { [0]=> string(2) "yr" } Warning: array_shift() [http://www.php.net/function.array-shift]: The argument should be an array in /in/tLLeK on line 4

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