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
>
>