dplyr::group_nest() is advised in Iteration chapter, but may become deprecated

[florisvdh]

In the Iteration chapter, dplyr::group_nest() is advised in order to restructure a data frame in such a way that rows represent the unique combinations of grouping variables and the remaining variables are moved to a list column (list of tibbles).

However the documentation of dplyr::group_nest() currently states:

group_nest() is not stable because tidyr::nest(.by =) provides very similar behavior. It may be deprecated in the future.

So I'd suggest to indeed use nest(.by =) (or group_by() |> nest()). I could make a pull request to implement that if you like.

[mine-cetinkaya-rundel]

For now, I'm going to tag this issue for the third edition. I don't think we need to update the content but we will revisit next time bigger changes are happening.