How to eval sexp in clojure-mode with cider and write result in current buffer

Question

For example I have the code:

(println "foo")

With cider-pprint-eval-last-sexp-to-comment I can eval the code and get

(println "foo") ;; nil

in clojure buffer and also it print foo in cider-repl buffer.

I would like to get something like this in the current buffer:

(println "foo") ;; nil foo

How can I do this?

Answer 1

You can use with-out-str to capture the output into a string.

user> (with-out-str
        (print "foo"))
"foo"

Knowing that you can take the cider-pprint-eval-last-sexp-to-comment function, copy/paste it and make a small change.

(define-key cider-mode-map (kbd "C-c C-p") 
  (lambda ()
    (interactive)
    (let* ((insert-before nil)
           (bounds (cider-last-sexp 'bounds))
           (insertion-point (nth (if insert-before 0 1) bounds))
           (comment-postfix (concat cider-comment-postfix
                                    (if insert-before "\n" ""))))
      (cider-interactive-eval (concat "(with-out-str " (cider-last-sexp) " )")
                              (cider-eval-pprint-with-multiline-comment-handler
                               (current-buffer)
                               (set-marker (make-marker) insertion-point)
                               cider-comment-prefix
                               cider-comment-continued-prefix
                               comment-postfix)
                              bounds
                              (cider--nrepl-print-request-map fill-column)))))

This function prints the captured output instead of the value. If you use it on something that doesn't write to *out* it will print the empty string.