function ValidateParameters($user, $password, $retypedPassword) { if (empty($user)) { return new Error(Error::InvalidParameter, "User name cannot be empty."); } if (UserFacade::IsUserRegistered($user)) { return new Error(Error::NotUniqueValue, "User with provided name is already registered."); } if (empty($password)) { return new Error(Error::InvalidParameter, "Password cannot be empty."); } if (strcmp($password, $retypedPassword)) { return new Error(Error::InvalidParameter, "Passwords don't match to each other."); } return new Error(); }