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<?php $a = array('xml' => array( 'attributes' => array( 'version' => '1.0', 'encoding' => 'utf-8', ), )); $a['attributes'] = array_merge($a['attributes'], array('test' => 'my_test_123')); var_dump($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 array key "attributes" in /in/ZMQpu on line 8 Fatal error: Uncaught TypeError: array_merge(): Argument #1 must be of type array, null given in /in/ZMQpu:8 Stack trace: #0 /in/ZMQpu(8): array_merge(NULL, Array) #1 {main} thrown in /in/ZMQpu on line 8
Process exited with code 255.
Output for 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
Notice: Undefined index: attributes in /in/ZMQpu on line 8 Warning: array_merge(): Expected parameter 1 to be an array, null given in /in/ZMQpu on line 8 array(2) { ["xml"]=> array(1) { ["attributes"]=> array(2) { ["version"]=> string(3) "1.0" ["encoding"]=> string(5) "utf-8" } } ["attributes"]=> NULL }
Output for 7.3.32 - 7.3.33, 7.4.26
Warning: array_merge(): Expected parameter 1 to be an array, null given in /in/ZMQpu on line 8 array(2) { ["xml"]=> array(1) { ["attributes"]=> array(2) { ["version"]=> string(3) "1.0" ["encoding"]=> string(5) "utf-8" } } ["attributes"]=> NULL }
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, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33
Notice: Undefined index: attributes in /in/ZMQpu on line 8 Warning: array_merge(): Argument #1 is not an array in /in/ZMQpu on line 8 array(2) { ["xml"]=> array(1) { ["attributes"]=> array(2) { ["version"]=> string(3) "1.0" ["encoding"]=> string(5) "utf-8" } } ["attributes"]=> NULL }
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Notice: Undefined index: attributes in /in/ZMQpu on line 8 Warning: array_merge(): Argument #1 is not an array in /in/ZMQpu on line 8 array(2) { ["xml"]=> array(1) { ["attributes"]=> array(2) { ["version"]=> string(3) "1.0" ["encoding"]=> string(5) "utf-8" } } ["attributes"]=> NULL }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9
Notice: Undefined index: attributes in /in/ZMQpu on line 8 array(2) { ["xml"]=> array(1) { ["attributes"]=> array(2) { ["version"]=> string(3) "1.0" ["encoding"]=> string(5) "utf-8" } } ["attributes"]=> array(1) { ["test"]=> string(11) "my_test_123" } }

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