我试图读取一个apache pig拉丁语文本文件，该文件的每一行都包含非分隔ascii。也就是说，该行中的每一列在该行的特定位置开始和结束。
样本定义：

+--------+----------------+--------------+
| Column | Start Position | End Position |
+--------+----------------+--------------+
| A      | 1              | 6            |
+--------+----------------+--------------+
| B      | 8              | 11           |
+--------+----------------+--------------+
| C      | 13             | 15           |
+--------+----------------+--------------+

样本数据：

+---+---+---+---+---+---+---+----+---+----+----+----+----+----+----+
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8  | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
+---+---+---+---+---+---+---+----+---+----+----+----+----+----+----+
| s | a | m | p | l | e |   | d  | a | t  | a  |    |    | h  | i  |
+---+---+---+---+---+---+---+----+---+----+----+----+----+----+----+
| d | u | d | e |   |   |   | hi |   |    |    |    | b  | r  | o  |
+---+---+---+---+---+---+---+----+---+----+----+----+----+----+----+

预期产量：

sample, data, hi
dude, hi, bro

我怎么读这个在Pig？pigstorage似乎不够灵活，不允许位置分隔，只允许字符串分隔（逗号、制表符等）。