is there an online compiler for R, where libraries are installed and you can upload data. I just found jdoodle.com (libraries are installed, but you can't upload csv-files) and online-ide.com (you can upload csv-files, but you can't use any libraries)
R is not a compiled programing language so you might be looking for the wrong key word. R is an interpreted language so R code gets executed by an R interpreter.
You haven't told us what is your specific use case but if you are looking for an online R session where you can use R interactively, you can use RStudio Cloud.
If you are looking for a working online R console that you can embed into a website for example, I know it is technically possible (Data Camp does it) but I'm not aware of a service that implements it for you.
Thanks for posting. I may be a bit confused what you mean by "compiler" in this instance. Are you looking for an online R interpreter, where you can feed data to an R program/enter R commands at a terminal? Then the easiest place to start is likely RStudio Server. If you are looking for an online compiler to say, send C code to and get a compiled executable program back, you may want to use something like onlinegdb. But if you need to compile code to run as R code, your best bet is just using RStudio Server and the Rcpp library.