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<?php $a = [ 'a' => [ 'a1' => 'a1', 'a2' => 'a2', 'a3' => 'a3', ], 'b' => [ 'b1' => 'b1', 'b2' => 'b2', 'b3' => 'b3', ], ]; $it = new RecursiveIteratorIterator(RecursiveArrayIterator($a, RecursiveArrayIterator::CHILD_ARRAYS_ONLY)); $b = []; foreach ($it as $key => $value) { $b[$key] = $value; } var_dump($b);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Fatal error: Uncaught Error: Call to undefined function RecursiveArrayIterator() in /in/uRZ8j:16 Stack trace: #0 {main} thrown in /in/uRZ8j on line 16
Process exited with code 255.
Output for 5.4.1 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Fatal error: Call to undefined function RecursiveArrayIterator() in /in/uRZ8j on line 16
Process exited with code 255.

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