Add `add-rows`?

[dbp]

Right now you can get all-rows, and then process rows as a list, but to turn the result back into a table, you need to .empty() (which seems reasonable) but then use foldr to repeatedly call add-row. Seems like add-rows could be added? .stack already exists.

[dbp]

Or, perhaps, would be better to provide something like this?

fun transform-rows(t :: Table, f :: (List<Row> -> List<Row>)) -> Table:
  new-rows = f(t.all-rows())
  new-rows.foldr(lam(r, t): t.add-row(r) end, t.empty())
end

Obviously we can put these in contexts, but seems odd that some version of this is not built in