ex.scala

    /**
     * Return the users that should receive a push after a Stample gets moved from one place to the other
     * @param movedStample the Stample that just got moved
     * @param movedBy the user that performed the move operation
     * @param from the former library/folder in which the folder was
     * @return the list of users to send a push message to
     */
    private def getUsersReceivingStampleMovePush(movedStample: Stample,movedBy: User,from: FolderLike): List[User] = {
      val formerLibrary = libraryService.getLibrary(from)
      val newLibrary = libraryService.getLibrary(movedStample)
      // If the stample is moved inside same library, we don't send any push
      if ( formerLibrary == newLibrary ) {
        Nil
      }
      else {
        libraryService.getLibraryMembers(library)
         .filterNot(_ == movedBy) // never send a push to the user performing the operation
      }
    }