When using the leiningen REPL, is there a way to make a file or ns automatically reload in the repl on file save. Currently I reload the ns by typing the following in the repl - (use 'sample.ns :reload-all).
However can I have it reload automatically on file save ?
You can easily reuse the code from duct framework.
You will need only hawk files watcher.
Here is how it can be looks like:
(defn- clojure-file? [_ {:keys [file]}]
(re-matches #"[^.].*(\.clj|\.edn)$" (.getName file)))
(defn- auto-reset-handler [ctx event]
(binding [*ns* *ns*]
(clojure.tools.namespace.repl/refresh)
ctx))
(defn auto-reset
"Automatically reset the system when a Clojure or edn file is changed in
`src` or `resources`."
[]
(hawk.core/watch! [{:paths ["src/" "resources/" "dev/src/" "dev/resources/"]
:filter clojure-file?
:handler auto-reset-handler}]))
Clojure-Watch library does what you need. It observes a file and performs some action. In your case, an action would be to reload a namespace from that file. Also, it requires to write some initial code to launch the observer.
This way seems a bit complicated to me. Plain REPL launched directly from Lein is not effective way to develop. You better to use some Clojure-friendly editor like Emacs or Lightable.
Most major editors support custom hotkey bindings and have a Clojure plugin that allows you to connect to the active REPL over the network (via "nREPL"). Personally, I use vim and therefore use vim-fireplace for this purpose.
This means you can have a custom hotkey for reloading whatever file you're editing as you edit it. From there, it's typically trivial to add a custom on-save hook that does the reloading.
