Customizing your REPL in clj
There was a question on Slack this evening about getting a similar effect to the injections feature of Leiningen in clj. There is no built-in feature for this, but you don’t really need one. The provided clojure.main/repl function is highly customizable. For example, it provides an
:eval hook, which defaults to just the
But that’s a great place to inject your own code around every eval, you’re almost there. At an existing repl, you can try a program like this to start a new nested repl with that function:
The :init hook replicates what clojure.main uses as an initial binding set, so it’s good to repeat that. The :eval hook just does an additional referral, making
pp always available.
You can start this as your actual repl at a command line by just smooshing it all together:
Or you can pack it into your deps.edn (using the Corfield comma as bash-safe whitespace):
It would be pretty easy to wrap this tiny program into a tool with the injections as an argument for reuse but not sure it’s worth that.