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<?php $a=array('a'=>1); $a=array('a'=>2); var_dump(array_merge($a,$b), array_merge($b,$a));
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
Warning: Undefined variable $b in /in/ML402 on line 4 Fatal error: Uncaught TypeError: array_merge(): Argument #2 must be of type array, null given in /in/ML402:4 Stack trace: #0 /in/ML402(4): array_merge(Array, NULL) #1 {main} thrown in /in/ML402 on line 4
Process exited with code 255.
Output for 7.3.12 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
Notice: Undefined variable: b in /in/ML402 on line 4 Warning: array_merge(): Expected parameter 2 to be an array, null given in /in/ML402 on line 4 Notice: Undefined variable: b in /in/ML402 on line 4 Warning: array_merge(): Expected parameter 1 to be an array, null given in /in/ML402 on line 4 NULL NULL
Output for 7.3.32 - 7.3.33, 7.4.26
Warning: array_merge(): Expected parameter 2 to be an array, null given in /in/ML402 on line 4 Warning: array_merge(): Expected parameter 1 to be an array, null given in /in/ML402 on line 4 NULL NULL
Output for 5.5.0 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33
Notice: Undefined variable: b in /in/ML402 on line 4 Warning: array_merge(): Argument #2 is not an array in /in/ML402 on line 4 Notice: Undefined variable: b in /in/ML402 on line 4 Warning: array_merge(): Argument #1 is not an array in /in/ML402 on line 4 NULL NULL
Output for 5.2.3 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45
Warning: array_merge(): Argument #2 is not an array in /in/ML402 on line 4 Warning: array_merge(): Argument #1 is not an array in /in/ML402 on line 4 NULL NULL
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.2
<br /> <b>Warning</b>: array_merge() [<a href='function.array-merge'>function.array-merge</a>]: Argument #2 is not an array in <b>/in/ML402</b> on line <b>4</b><br /> <br /> <b>Warning</b>: array_merge() [<a href='function.array-merge'>function.array-merge</a>]: Argument #1 is not an array in <b>/in/ML402</b> on line <b>4</b><br /> NULL NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9
array(1) { ["a"]=> int(2) } array(1) { ["a"]=> int(2) }
preferences:
260.72 ms | 402 KiB | 344 Q