Emacs+ESS idle time print

How can I make Emacs execute something like

(ess-eval-linewise "cat(date(), '\\n')" t nil nil nil)

each time ess is running and Emacs has been idle for a certain amount of time and somewhere ar开发者_如何学编程ound the moment it stops being idle?

I have no experience with ess but you can use run-with-idle-timer to run a command when Emacs has been idle for a given amount of time.

You can wrap the line above in a function and give it to this function and have it execute everytime Emacs is idle for the given amount of time.

For details on using the function, take a look at the wiki.