[O] Bug: Empty result when Emacs Lisp code block evals to nil [9.0.5 (release_9.0.5-401-g86ff11 @ /Users/xcy/src/org-mode/lisp/)]

[Chunyang Xu]

Hi.

I notice that if the result is nil during executing emacs-lisp code
block, org simply displays a empty #+RESULT block. For example,


#+BEGIN_SRC emacs-lisp
t
#+END_SRC

#+RESULTS:
: t

#+BEGIN_SRC emacs-lisp
nil
#+END_SRC

#+RESULTS:


I don't see why 'nil' is special than other values like 't'.


--
Emacs  : GNU Emacs 26.0.50 (build 10, x86_64-apple-darwin16.4.0, NS 
appkit-1504.81 Version 10.12.3 (Build 16D32))
 of 2017-03-28
Package: Org mode version 9.0.5 (release_9.0.5-401-g86ff11 @ 
/Users/xcy/src/org-mode/lisp/)