Question: I want to produce a table with `knitr::kable` with vertical lines on the borders and between certain columns. Is there a way to do it?
My output document is pdf.

Thanks!

Answer: 
Not too much clear, but maybe this could help:

```
library(knitr)
library(kableExtra)
library(dplyr)

dt <- mtcars[1:5, 1:6]
dt %>% 
kable() %>%
# here you can add the vertical line, in my example, for all the columns
column_spec (1:7,border_left = T, border_right = T) %>%
kable_styling()

```

[![enter image description here](https://i.stack.imgur.com/jpwpI.png)](https://i.stack.imgur.com/jpwpI.png)

And if you need to save it as `.pdf`:

```
save_kable(k, "k.pdf")

```

With `k` as the result of the code above.
Answer using huxtable:

```
library(huxtable)
library(dplyr)

as_hux(mtcars[1:5, 1:6], add_colnames = TRUE) %>%
      set_right_border(2:5, everywhere, 0.4) %>%
      set_bottom_border(1, everywhere, 0.4)

```

You can then save it to PDF with `quick_pdf()`, or print it within a rmarkdown document.