2-column source->target dataframe to link and node lists?

Is there a native munging function for getting a 2-column (source->target) data.frame into a link list and node list format?

The 2-column dataframe has the following format

| Source | Target |
|--------|--------|
| A | C |
| A | D |
| B | E |
| B | F |

The link list would be:

| from | to |
|------|----|
| 0 | 2 |
| 0 | 3 |
| 1 | 4 |
| 1 | 5 |

and the node list would be

| id | node |
|----|------|
| 0 | A |
| 1 | B |
| 2 | C |
| 3 | D |
| 4 | E |
| 5 | F |

I can get the data into this format but I want to know if there are standard methods for doing so?