how to unlist a `tknlist`? - tidyverse

Question

step_tokenize returns a vector of type tknlist. How can I get a rectangular for of it? I mean something like unnesting the tokens and add them a cols of the tibble.
library(textrecipes)
library(modeldata)
data(tate_text)
tate_rec <- recipe(~., data = tate_text) %>%
step_tokenize(medium) %>%
show_tokens(medium)
tate_obj <- tate_rec %>%
prep()
dd <- bake(tate_obj, new_data = NULL, medium)

Answer 1

There is not a direct way to get a rectangle from a tknlist object in {textrecipes}. The object is mainly used internally in the package.
You can use the unexported textrecipes:::get_tokens() function to turn the tknlist object into a list of character tokens. But the package doesn't have any functions that let unnest that object.
library(textrecipes)
library(modeldata)
data(tate_text)
tate_rec <- recipe(~., data = tate_text) %>%
step_tokenize(medium)
tate_obj <- tate_rec %>%
prep()
dd <- bake(tate_obj, new_data = NULL, medium, everything())
dd
#> # A tibble: 4,284 × 5
#> medium id artist title year
#> <tknlist> <dbl> <fct> <fct> <dbl>
#> 1 [8 tokens] 21926 Absalon Proposals for a Habitat 1990
#> 2 [3 tokens] 20472 Auerbach, Frank Michael 1990
#> 3 [3 tokens] 20474 Auerbach, Frank Geoffrey 1990
#> 4 [3 tokens] 20473 Auerbach, Frank Jake 1990
#> 5 [4 tokens] 20513 Auerbach, Frank To the Studios 1990
#> 6 [4 tokens] 21389 Ayres, OBE Gillian Phaëthon 1990
#> 7 [4 tokens] 121187 Barlow, Phyllida Untitled 1990
#> 8 [3 tokens] 19455 Baselitz, Georg Green VIII 1990
#> 9 [6 tokens] 20938 Beattie, Basil Present Bound 1990
#> 10 [3 tokens] 105941 Beuys, Joseph Joseph Beuys: A Private Collectio… 1990
#> # … with 4,274 more rows
dd %>%
mutate(medium = textrecipes:::get_tokens(medium))
#> # A tibble: 4,284 × 5
#> medium id artist title year
#> <list> <dbl> <fct> <fct> <dbl>
#> 1 <chr [8]> 21926 Absalon Proposals for a Habitat 1990
#> 2 <chr [3]> 20472 Auerbach, Frank Michael 1990
#> 3 <chr [3]> 20474 Auerbach, Frank Geoffrey 1990
#> 4 <chr [3]> 20473 Auerbach, Frank Jake 1990
#> 5 <chr [4]> 20513 Auerbach, Frank To the Studios 1990
#> 6 <chr [4]> 21389 Ayres, OBE Gillian Phaëthon 1990
#> 7 <chr [4]> 121187 Barlow, Phyllida Untitled 1990
#> 8 <chr [3]> 19455 Baselitz, Georg Green VIII 1990
#> 9 <chr [6]> 20938 Beattie, Basil Present Bound 1990
#> 10 <chr [3]> 105941 Beuys, Joseph Joseph Beuys: A Private Collection… 1990
#> # … with 4,274 more rows