With this package, you can control error codes and exceptions in system with many sub systems.

Add FivePercent/Error in your composer.json:

{
    "require": {
        "fivepercent/error": "~1.0"
    }
}

Now tell composer to download the library by running the command:

$ php composer.phar update fivepercent/error

For collect all error codes, you must create a error factory in you sub system:

use FivePercent\Component\Error\ErrorFactoryInterface;

final class MySystemError implements ErrorFactoryInterface
{
    const ERROR_1 = 1;
    const ERROR_2 = 2;

    public function getErrors()
    {
        return [
            self::ERROR_1 => 'Error #1',
            self::ERROR_2 => 'Error #2'
        ];
    }

    public function getExceptions()
    {
        return [];
    }

    public function getReservedDiapason()
    {
        return [1, 5];
    }
}

And create error system (Storage), and add this factory to storage:

use FivePercent\Component\Error\Errors;

$errors = new Errors();
$errors->addFactory(new MySystemError());

After, you can:

1. Get reserved diapasons for each system

   $errors->getReservedCodes();

2. Get all errors for system

   $errors->getErrors();

3. Get all exceptions

   $exceptions = $errors->getExceptions();

4. Check, if has exception in errors storage

   $exception = new \Exception();
   $errors->hasException($exception);

5. Get error code for exception

   $exception = new \Exception();
   $code = $errors->getExceptionCode($exception);

6. Check reserved codes

   $errors->checkReservedCodes();