src/Interval.php
public function step($step = null)
    {
        if (isset($step)) {
            $this->step = $step;
            return $this;
        } else {
            return $this->step;
        }
    }
public function step($step = null)
    {
        if (isset($step)) {
            $this->step = $step;
            return $this;
        } else {
            return $this->step;
        }
    }
public function step ( $ step = null ) { if ( isset ( $ step ) ) { $ this -> step = $ step ; return $ this ; } else { return $ this -> step ; } }
Set or get the step of the interval

@param null $step
@return $this|null
Set or get the step of the interval