nrepl_additions.el

(defun nrepl-interactive-eval-print-comment-handler (buffer)
  (nrepl-make-response-handler buffer
                               (lambda (buffer value)
                                 (with-current-buffer buffer
                                   (insert (format " ;; %s" value))))
                               '()
                               (lambda (buffer err)
                                 (message (format " ;; %s" err)))
                               '()))

(defun nrepl-interactive-eval-print-comment (form)
  "Evaluate the given form and print value in current buffer."
  (let ((buffer (current-buffer)))
    (nrepl-send-string form
                       (nrepl-interactive-eval-print-comment-handler buffer)
                       nrepl-buffer-ns)))

(defun nrepl-eval-region-comment (start end)
   "Evaluate region."
   (interactive "r")
   (nrepl-interactive-eval-print-comment (buffer-substring-no-properties start end)))