FWIW Cursive doesn’t use any middleware at all.

I’m a big fan of loading the server-side code I need over the REPL connection when it’s opened.

But tooling like CIDER that uses the REPL more than Cursive does are very prone to this sort of problem, right.

Never thought of it that way, static analysis saves you from having to do a lot of the server side stuff.

I don’t think there’s a solution other than saying “this functionality won’t work unless you’re using Clojure 1.9+"

Yeah

Generally I try to make sure that Cursive will work independently of the version of Clojure the user is using.

I’m actually looking at some REPL improvements right now, and if I want to use EDN then that means a Clojure 1.5+ project. Fortunately I know which version the user is using and can warn them, but it’s a little ugly.

@tbaldridge BTW pure socket REPLs are on the way.

(in Cursive)

But again, there I have to check that the user is using 1.8+

is there a way to grab the :ret spec out of an fdef? trying to validate the return value of a fn in a test

Yep, just call get-spec on the symbol to get the function spec

That spec implements ILookup and can be invoked with :ret

So, (:ret (s/get-spec 'full/symbol))