@bozhidar you have any suggestions for my problem, where I'd like to prevent a value which implements IDeref from being derefed when it's pretty printed as a return value in cider?

I can look in a bit but I’m guessing it’s an extend method we added to the print mechanism. Should be overridqble back and that is a bug in my view

Hmm. This sounds weirder and weirder. Since derefing can trigger blocking and on delays can trigger computation prematurely.

Yeah, I also implement IBlockingDeref and that impl isn't used ever

The problem is I'm trying to implement custom promises in order to prevent a breaking change to my api, but I don't want to have to require my users have cider or nrepl on their classpath to run the application, but I also don't want it to hang if they try something out on the repl

Yeah agreed

Hopefully there’s a way to fix up in code without waiting on a release

(def ^:dynamic pretty-objects "If true, cider prettifies some object descriptions. For instance, instead of printing functions as #object[clojure.core$PLUS 0x4e648e99 \"clojure.core$PLUS@4e648e99\"] they are printed as #function[clojure.core/+] To disable this feature, do (alter-var-root #'cider.nrepl.print-method/pretty-objects not)" true)

https://github.com/clojure-emacs/cider-nrepl/blob/master/src/cider/nrepl/print_method.clj

You can turn it off with that dynamic var. can probably easily redef the print-method for ideref in your repl and that should be removed I think

@suskeyhose i'm looking into this some more. I see that the printer for the c.l.IDeref checks to see if a) its also IPending and b) if so, if its realized. (https://github.com/clojure/clojure/blob/master/src/clj/clojure/core_print.clj#L436-L457). Is it possible for you to also add IPending to your custom promise types such that the printer works better? I still think this is a bug in cider-nrepl but this also might allow you to add a bit more onto your type to make it a bit better as well

I'm actually less convinced this is a bug. in a bare clj repl:

~/p/d/cider-nrepl ❯❯❯ clj
Clojure 1.10.1
user=> (reify clojure.lang.IDeref (deref [_] (do (prn "i'm gonna sleep a while") (Thread/sleep 3000) :slept/value)))
"i'm gonna sleep a while"
#object[user$eval136$reify__137 0x29182679 {:status :ready, :val :slept/value}]
user=>

Seems I’m late to this conversation and you’ve made plenty of progress without me. Might be a good idea to move this to some issue, so that the important points won’t get lost with the Slack history.

cross post alert! posted in #clojurescript, too...

to try the code at https://www.learn-clojurescript.com/section-1/lesson-8-capstone-weather-forecasting-app/ I created the project with

lein new figwheel cljs-weather -- --reagent

yarn

cider-jack-in-clj&cljs

Caused by java.lang.RuntimeException
   Unable to resolve symbol: GET in this context

@patrickanium I guess you forgot to load the buffer first (`C-c C-k`) and your requires are not in scope.

I've defined a record named Foo with a print-method and in the cider repl, it seems to ignore my print-method . Is that normal? My emacs value of cider-print-fn is pprint and I have not set this value anywhere. Its the value out-of-the-box as far as I know.

Ah nevermind, it was my own user.clj causing the issue... But anyway, CIDER is still broken with the most recent shadow-cljs ("missing instance")

@dpsutton Thanks for the tip! Just implementing a basic implementation of IPending fixes the issue.

Hi all, lein 2.9.3 depends on nREPL 0.6.0 (https://github.com/technomancy/leiningen/blob/2.9.3/project.clj#L21) and the most recent version of cider-nrepl v0.25.2 depends on nREPL 0.7.0 (https://github.com/clojure-emacs/cider-nrepl/blob/v0.25.2/project.clj#L7) ... how I can deal with this conflict if my project.clj defines :pedantic? :abort ?

@bozhidar how do I get the requires in scope?

I loaded the buffer with C-c C-k but it errors on the first form (the ns one with the require).

whoa... just changed to clojurescript-mode (M-x clojurescript-mode) and it works!

thanks for the help 🙂