public function leftJoinSub($query, $as, $first, $operator = null, $second = null)
    {
        return $this->joinSub($query, $as, $first, $operator, $second, 'left');
    }
public function leftJoinSub($query, $as, $first, $operator = null, $second = null)
    {
        return $this->joinSub($query, $as, $first, $operator, $second, 'left');
    }
public function leftJoinSub ( $ query , $ as , $ first , $ operator = null , $ second = null ) { return $ this -> joinSub ( $ query , $ as , $ first , $ operator , $ second , 'left' ) ; }
Add a subquery left join to the query.

@param  \Closure|\Illuminate\Database\Query\Builder|string $query
@param  string  $as
@param  \Closure|string  $first
@param  string|null  $operator
@param  string|null  $second
@return \Illuminate\Database\Query\Builder|static
Add a subquery left join to the query .