protected function _loop()
    {
        $tracker = $this->_getTracker();
        $this->_advanceTracker($tracker);
        $iteration = $this->_createIterationFromTracker($tracker);

        return $iteration;
    }
protected function _loop()
    {
        $tracker = $this->_getTracker();
        $this->_advanceTracker($tracker);
        $iteration = $this->_createIterationFromTracker($tracker);

        return $iteration;
    }
protected function _loop ( ) { $ tracker = $ this -> _getTracker ( ) ; $ this -> _advanceTracker ( $ tracker ) ; $ iteration = $ this -> _createIterationFromTracker ( $ tracker ) ; return $ iteration ; }
Advances the loop and calculates the next iteration.

@since [*next-version*]

@throws RootException If problem looping.

@return IterationInterface The iteration that represents the new state.
Advances the loop and calculates the next iteration .