/**
* @return $this
*/
public function prepare()
{
$this->progress = new ProgressBar($this->output, $this->reader->count());
$this->progress->setFormat($this->verbosity);
$this->progress->setRedrawFrequency($this->redrawFrequency);
$this->progress->start();
return $this;
}
/**
* Count elements of an object
* The return value is cast to an integer.
*/
public function count()
{
return $this->leftReader->count();
}
