Using cursor instead of pagination with Fractal. IE: GET /users?cursor=5

ApiController.php

<?php

use League\Fractal\Manager;
use League\Fractal\Resource\Collection;
use League\Fractal\Resource\Item;
use League\Fractal\Cursor\CursorInterface;

class ApiController extends Controller
{
  
    public function __construct()
    {
        $this->fractal = new Manager;

        $this->fractal->setRequestedScopes(explode(',', Input::get('include')));
    }
    
    protected function respondWithCursor($collection, $callback, CursorInterface $cursor)
    {
        $resource = new Collection($collection, $callback);
        $resource->setCursor($cursor);

        $rootScope = $this->fractal->createData($resource);

        return $this->respondWithArray($rootScope->toArray());
    }
    
}

cursor_5.json

{
    "data": [
        {
            "id": 6,
            "name": "Lennie Raynor PhD"
        },
        {
            "id": 7,
            "name": "Duncan Raynor"
        },
        {
            "id": 8,
            "name": "clockman"
        },
        {
            "id": 9,
            "name": "Gerard Marks DDS"
        },
        {
            "id": 10,
            "name": "josefina32"
        }
    ],
    "cursor": {
        "current": 5,
        "next": 10,
        "count": 5
    }
}

empty_cursor.json

{
    "data": [
        {
            "id": 1,
            "name": "Isern Palaus"
        },
        {
            "id": 2,
            "name": "Lorem Ipsum"
        },
        {
            "id": 3,
            "name": "Javi Martinez"
        },
        {
            "id": 4,
            "name": "lowe.yasmin"
        },
        {
            "id": 5,
            "name": "abshire.durward"
        }
    ],
    "cursor": {
        "current": 0,
        "next": 5,
        "count": 5
    }
}

UsersController.php

<?php

use League\Fractal\Cursor\Cursor;

class UsersController extends ApiController
{

    public function index()
    {
        $current = Input::get('cursor', false);

        $users = new User;

        if ($current and is_numeric($current)) {
            $users = $users->where('id', '>', $current);
        }

        $users = $users->take(20)->get();

        $cursor = new Cursor($current, $users->last()->id, $users->count());

        return $this->respondWithCursor($users, new UserTransformer, $cursor);
    }
    
}

?? eturn $this->respondWithArray($rootScope->toArray()); ?? I can not find this line of code APiController