The code examples in my book Learn R …as you learnt your mother tongue continue to work as expected. However not all the package updates for R 3.4.0 are yet in CRAN. In package ‘gganimate’ function gg_animate() has been renamed gganimate().
It is always best to keep R up-to-date. This is not a major release, but instead mostly a bug fix release.
If you are using R on MS-Windows then you can very painlessly upgrade R with package ‘installr’. These are the needed steps, that should be carried out not in RStudio but in RGUI (i.e. double click the R icon on your desktop).
At the console enter:
install.packages("installr") # install
setInternet2(TRUE) # only for R versions older than 3.3.0
installr::updateR() # updating R.
Follow the prompts. I suggest that you copy and update the packages in the library.