# Concerns

Most of the export/import configuration is done by using Concerns.

# Contracts

Concerns are basically just simple interfaces. Implementing them will make the object adhere to a certain contract. This contract can request specific methods that e.g. data can be passed through.

For instance, the FromCollection requests the Export object to implement a collection method, that needs to return a Collection instance.

namespace App\Exports;

use App\User;
use Nikazooz\Simplesheet\Concerns\FromCollection;

class UsersExport implements FromCollection
{
    public function collection()
    {
        return User::all();
    }
}