ClojureScript Node.js vim repl

August 1, 2015

There are lots of great "plug-and-play" setups for ClojureScript in the browser, like Figwheel and Chestnut. However, getting a good REPL environment for ClojureScript targeting Node.js seemed quite under-documented. After consulting numerous resources (many of which, uh, how should I say, may or may not have been really outdated), here's how I did it:

  1. Get a starter ClojureScript Project
    $ lein new mies replicious
  2. Follow basic directions in the README.md
    • in particular, run lein npm install
    • also just a note: if you try to run ./scripts/repl as advertised in the README it won't work! To fix it, you need to alter the ./scripts/repl.clj file by changing the function call from `(repl/repl* ...) to (repl/repl ...)`.
  3. Include Cemerick's piggieback
    • Add this snippet to your project.clj
      :profiles  {:dev  {:dependencies  [[com.cemerick/piggieback "0.2.1"]
                                     [org.clojure/tools.nrepl "0.2.10"]]
                     :repl-options  {:nrepl-middleware  [cemerick.piggieback/wrap-cljs-repl]}}}
  4. In the repl, do the following:
    $ lein repl
...
user=> (require '[cljs.repl.node :as node])
nil
  5. In fireplace, run
    :Piggieback (node/repl-env)
  6. Try it out!
    • One last roadblock I encountered was the issue described here.
    • I fixed it by simply updating to the latest version of fireplace :) (almost too easy!).

I think this is actually the first time I've successfully gotten fireplace to connect to a ClojureScript repl. I remember having some trouble connecting fireplace to the browser repls provided by figwheel/chestnut, so in those environments, I just live reload stuff and observe the output of the web console. Fast enough, but I think this will be even better :).