No, it's not expected result. It should be caused by my commit here https://code.orgmode.org/bzg/org-mode/pulls/5
Don't know how to workaround this.

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On Thu, Mar 1, 2018 at 11:50 PM, Xu Chunyang <mail@xuchunyang.me> wrote:
Hello all,

I run the following Clojure code with CIDER as the backend. The result
is surprising to me:

    #+begin_src clojure
    (* 6 7)
    (= nil ())
    #+end_src

    #+RESULTS:
    : 42false

As you can see, the result is the concatenation of the value of each
expression. Is it expected? I would like to get only the value of the
last expression, i.e., false.


--
Org   release_9.1.7-440-g5e8fa1361
CIDER v0.16.0-83-g88f4fcf
Emacs 27.0.50