We can run bookdown::render_book("index.Rmd", "bookdown::pdf_book") and it will create a pdf for us at any point. It will not automatically create it when we build the book, though. This is because of how I got it to work, which is changing the eval statement to only evaluate the embedded links when is_html_output() = TRUE. That is equal to TRUE when we do the classic build book, but not when we build a pdf book, which is why it wont build the pdf (i get the classic error) when we build it in our normal way, but it DOES build the pdf when I do that manually.
We can run bookdown::render_book("index.Rmd", "bookdown::pdf_book") and it will create a pdf for us at any point. It will not automatically create it when we build the book, though. This is because of how I got it to work, which is changing the eval statement to only evaluate the embedded links when is_html_output() = TRUE. That is equal to TRUE when we do the classic build book, but not when we build a pdf book, which is why it wont build the pdf (i get the classic error) when we build it in our normal way, but it DOES build the pdf when I do that manually.