text: <?php
  
  /*
   * This file is part of the Symfony package.
   *
   * (c) Fabien Potencier <fabien@symfony.com>
   *
   * For the full copyright and license information, please view the LICENSE
   * file that was distributed with this source code.
   */
  
  namespace Symfony\Component\Translation\Catalogue;
  
  use Symfony\Component\Translation\MessageCatalogueInterface;
  
  /**
   * Represents an operation on catalogue(s).
   *
   * An instance of this interface performs an operation on one or more catalogues and
   * stores intermediate and final results of the operation.
   *
   * The first catalogue in its argument(s) is called the 'source catalogue' or 'source' and
   * the following results are stored:
   *
   * Messages: also called 'all', are valid messages for the given domain after the operation is performed.
   *
   * New Messages: also called 'new' (new = all ∖ source = {x: x ∈ all ∧ x ∉ source}).
   *
   * Obsolete Messages: also called 'obsolete' (obsolete = source ∖ all = {x: x ∈ source ∧ x ∉ all}).
   *
   * Result: also called 'result', is the resulting catalogue for the given domain that holds the same messages as 'all'.
   *
   * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
   */
  interface OperationInterface
  {
      /**
       * Returns domains affected by operation.
       *
       * @return array
       */
      public function getDomains();
  
      /**
       * Returns all valid messages ('all') after operation.
       *
       * @param string $domain
       *
       * @return array
       */
      public function getMessages($domain);
  
      /**
       * Returns new messages ('new') after operation.
       *
       * @param string $domain
       *
       * @return array
       */
      public function getNewMessages($domain);
  
      /**
       * Returns obsolete messages ('obsolete') after operation.
       *
       * @param string $domain
       *
       * @return array
       */
      public function getObsoleteMessages($domain);
  
      /**
       * Returns resulting catalogue ('result').
       *
       * @return MessageCatalogueInterface
       */
      public function getResult();
  }
  