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<?php $input = Array( Array ( array(0 => 1) ), Array ( array(0 => 2) ) ); $result = call_user_func_array("array_merge", $input); var_export($result);
Output for 4.3.0 - 7.2.0
array ( 0 => array ( 0 => 1, ), 1 => array ( 0 => 2, ), )