PHP / Laravel 5.1 - 无法重新声明先前在文件中声明的方法

I am writing a helper method to read and convert a xml data into json. I followed the steps below

1) Created file

app/helper/commonHelper.php

and added following code to it.

<?php

function xmlToArray($xml, $options = array()) {
// the entire code here

}

2) Created a file under

app/providers/HelperCommonsProvider.php

and following code

<?php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;

class HelperCommonsProvider extends ServiceProvider
{
    /**
     * Bootstrap the application services.
     *
     * @return void
     */
    public function boot()
    {
        //
    }

/**
 * Register the application services.
 *
 * @return void
 */
public function register()
{
   require base_path().'/app/Helpers/CommonHelper.php';
}

}

Now when I call xmlToArray() in the controller like

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Http\Requests;
use Tymon\JWTAuth\Facades\JWTAuth;
use Illuminate\Support\Facades\Config;
use Log as EventLogger;
class UsersController extends Controller {

    /**
     * Display a listing of the resource.
     *
     * @return Response
     */

    public function index() {
        echo "You are in the index function";

            $file = Config::get('constants.constants.userdirectory');
            $file  = $file . '/' . 71 . '/' . 71 . '.xml' ;



            $xmlloaded = simplexml_load_file($file);


            $returnvalues =  xmlToArray($xmlloaded, array('alwaysArray'));
            echo json_encode($returnvalues);
            die;

        //
    }
}

This throws an exception

Fatal error:  Cannot redeclare xmlToArray() (previously declared in D:\work\HC\hcserver\app\Helpers\CommonHelper.php:3) in

D:\work\HC\hcserver\app\Helpers\CommonHelper.php on line 79 PHP Fatal error: Uncaught exception 'Illuminate\Contracts\Container\BindingResolutionException' with message 'Target [Illuminate\Contracts\Debug\ExceptionHandler] is not instantiable.' in D:\work\HC\hcserver\vendor\laravel\framework\src\Illuminate\Container\Container.php:748

Please tell me what am I doing wrong here?

UPDATED: Entire content inside CommonHelper.php -> http://pastebin.com/GuQGYnJP

you should change name from

xmlToArray to xmlToArrayCustom

Reason: its global function which make sense to laravel and php. because this method name is used by PHP Library and cannot be redaclared with the same name.