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<?php $a = array('a' => "test", 'b' => 'aa'); $a = array_merge($a['a'], array('bb' => "gdaf")); 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 - 8.3.7
Fatal error: Uncaught TypeError: array_merge(): Argument #1 must be of type array, string given in /in/iKQZO:3 Stack trace: #0 /in/iKQZO(3): array_merge('test', Array) #1 {main} thrown in /in/iKQZO on line 3
Process exited with code 255.
Output for 7.3.12 - 7.3.33, 7.4.0 - 7.4.33
Warning: array_merge(): Expected parameter 1 to be an array, string given in /in/iKQZO on line 3 NULL
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33
Warning: array_merge(): Argument #1 is not an array in /in/iKQZO on line 3 NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9
array(2) { [0]=> string(4) "test" ["bb"]=> string(4) "gdaf" }

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