Evaluation in debugger must be done within the namespace of instrumented form

[vspinu]

Do in a tmp.clj (user namespace)

(defn foo [a]
  (bar a))

(defn bar [b]
  (+ 1 b))

Then from another namespace do (foo 1) once you are after (bar a) eval with C-x C-e. you should get Unable to resolve symbol: bar in this context.

It's probably easy to fix. Will have a look once clojure-emacs/cider-nrepl#405 is merged.