Hello,

I have integrated some of the ob-session-async package in ob-R.el
(finally). Most of the heavy lifting has been made by Jack.


So with the patch async evaluation is  expected to work out of the box
for :result value

#+begin_src R :session *R*  :results value :async :colnames yes
Sys.sleep(10)
as.list(1:5)
#+end_src

#+RESULTS:
| x |
|---|
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |

But for the time being result output produces the following output.

#+begin_src R :session *R*  :results output :async
Sys.sleep(1)
print(1:5)
#+end_src

#+RESULTS:
: > Sys.sleep(1)
: > print(1:5)
: [1] 1 2 3 4 5
: > 'ob_comint_async_R_end_53c0a42fed17cf78f5508e5293029430'


From my understanding the async command of python does not suffer from
this issue. I'm not sure if the issue needs to be solve at the ob-R.el
or at the ob-core.el. I welcome any comments on this patch or any idea
to move it forward.

Best regards,
Jeremie