Status of this project

[SylvianHemus]

Just curious -- what's the status of Arcadia? It hasn't been updated for a few years. Is it complete at this point?

[TheWitheredStriker]

It seems to have been abandoned by the developers, although it still works as it should on Unity 2021.3 LTS (not on 2022.1 though). Some people in the community have considered forking it for continued maintenance, but nothing has come of it so far. I do not have the experience to do that at the moment and others seem not to have the time.

For now, Arcadia is largely abandonware, but I hope that this will change in the future. If I ever get to a point where I have both the skill and the time to fork/maintain it, I will, but for now I can't do much.

[darthdeus]

Any idea how difficult it would be to make it work on 2022.1, or what are the reasons for it not working there? I'm relatively new to Clojure but know a bit about Unity, so I'm curious what change Unity introduced that caused Arcadia to break.

[TheWitheredStriker]

I don't know the details. All I can tell you is that Arcadia is now prevented from running play mode. I wish I could help you more.

[TheWitheredStriker]

@darthdeus I have asked around in the Arcadia chatroom over at Gitter for you. I highly recommend joining it if you are interested in Arcadia, even if the group isn't super active. It'll make coordination a bit easier :) https://gitter.im/arcadia-unity/Arcadia

[kamisori]

i mean, have you seen what tims is working on now? https://www.youtube.com/watch?v=Mc2r2qmC0y4 live edit games as they run

https://www.youtube.com/watch?v=Y3qadZY8inY

[Folcon]

@darthdeus so I had a project working with unity 2021.2.1f1, not seen any issues.

Just tried it with 2022.1.20f1 with the instructions here.

It seems to load and work fine?

What problems are you seeing?

I'm not an arcadia core dev, but I have been keeping an eye on the project =)...

[TheWitheredStriker]

That's strange. I've heard from @ekhart that Arcadia no longer works for him. Perhaps he can give us some more info.

[darthdeus]

Okay so I tried it, I ran into one error after adding Arcadia in Unity 2022.1.17f1 (just downloaded the latest release zip and copy pasted into assets). The error was

PrecompiledAssemblyException: Multiple precompiled assemblies with the same name Ionic.Zip.dll included on the current platform. Only one assembly with the same name is allowed per platform.

I clicked on the Ionic.Zip.dll in the arcadia folder, disabled it, and the error went away and it seems to start nREPL that I can connect to from emacs? I'm not entirely sure if it's working because I kinda ran out of time and needed to do different things for a few days, but I wonder if this is the error others ran into, or if there are other problems?

[Folcon]

Hi @darthdeus, possible? I think I've seen that error before.

The reason I pointed specifically to the instructions I used previously is that I know they produce a working output on my side. It would be good to shake out any issues with the process and fix them.

[darthdeus]

A little update, after a little bit of fiddling I got it to somewhat work, basically just ran this

user> (use 'arcadia.core)
user> (import '[UnityEngine GameObject Time Mathf Transform Vector3])
user> (set! (.. (object-named "Player") transform position) (Vector3.))

and saw the player move. All it took was disabling the Ionic.Zip, which I configured like this for Arcadia to compile

Seems there's a lot of errors from fiddling with the REPL though

Here's the two stacktraces for anyone who wants to look into things

TypeNotFoundException: Unable to find type: clojure.stacktrace
clojure.lang.RT.classForNameE (System.String p) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
clojure.lang.CljCompiler.Ast.HostExpr.MaybeType (System.Object form, System.Boolean stringOk) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
clojure.lang.Compiler.MacroexpandSeq1 (clojure.lang.ISeq form) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
clojure.lang.Compiler.macroexpand1 (System.Object form) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
clojure.lang.Compiler.Macroexpand (System.Object form) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
clojure.lang.Compiler.eval (System.Object form) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
clojure$core$eval__3112.invokeStatic (System.Object ) (at <f25e268922394fd0aa90bd66a9e9327d>:0)
clojure$core$eval__3112.invoke (System.Object ) (at <f25e268922394fd0aa90bd66a9e9327d>:0)
clojure.lang.Var.invoke (System.Object arg1) (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
Arcadia.NRepl+EvalFn.invoke () (at Assets/Plugins/Arcadia/Editor/NRepl.cs:299)
arcadia$internal$callbacks$run_callbacks__28828.invokeStatic (System.Object , System.Object ) (at <f25e268922394fd0aa90bd66a9e9327d>:0)
arcadia$internal$callbacks$run_callbacks__28828.invoke (System.Object , System.Object ) (at <f25e268922394fd0aa90bd66a9e9327d>:0)
arcadia$internal$editor_callbacks$run_callbacks__28922.invokeStatic () (at <f25e268922394fd0aa90bd66a9e9327d>:0)
arcadia$internal$editor_callbacks$run_callbacks__28922.invoke () (at <f25e268922394fd0aa90bd66a9e9327d>:0)
clojure.lang.Var.invoke () (at <fb1204dbf0b848beaab1559f81f1b22c>:0)
Arcadia.EditorCallbacks.RunCallbacks () (at Assets/Plugins/Arcadia/Editor/EditorCallbacks.cs:24)

and second one

NullReferenceException: Object reference not set to an instance of an object
Arcadia.NRepl.HandleMessage (BencodeNET.Objects.BDictionary message, System.Net.Sockets.TcpClient client) (at Assets/Plugins/Arcadia/Editor/NRepl.cs:471)
Arcadia.NRepl+<>c__DisplayClass36_0.<StartServer>b__1 () (at Assets/Plugins/Arcadia/Editor/NRepl.cs:580)
UnityEngine.Debug:LogException(Exception)
Arcadia.<>c__DisplayClass36_0:<StartServer>b__1() (at Assets/Plugins/Arcadia/Editor/NRepl.cs:584)
System.Threading.ThreadHelper:ThreadStart()

In either case, I'm a little scared to proceed, so I'll just put my Arcadia exploration on hold until/if the situation stabilizes a bit :) I'm currently a little scared to play with it more since this is a non-trivially sized game that'll be released in a few months at most.

[TheWitheredStriker]

https://github.com/arcadia-unity/Arcadia/tree/ifrit

Interesting – this appears to be an active branch of Arcadia ahead of the main branch, and one of the main devs (@timsgardner) actually contributed to it as recent as last November. Does this branch have the same issues as the main one?

[benjamin-asdf]

Arcadia.NRepl.HandleMessage (BencodeNET.Objects.BDictionary message, System.Net.Sockets.TcpClient client) (at Assets/Arcadia/Editor/NRepl.cs:398)
Arcadia.NRepl+<>c__DisplayClass36_0.<StartServer>b__1 () (at Assets/Arcadia/Editor/NRepl.cs:580)
UnityEngine.Debug:LogException(Exception)
Arcadia.<>c__DisplayClass36_0:<StartServer>b__1() (at Assets/Arcadia/Editor/NRepl.cs:584)
System.Threading.ThreadHelper:ThreadStart()

This is when cider asks for eldoc or info. I have fixed and improved this #389

• TypeNotFoundException: Unable to find type: clojure.stacktrace

This is because cider tries to pretty print a stacktrace but resolving clojure.stacktrace/print-cause-trace throws an error at that point.

(defun cider-default-err-eval-handler ()
  "Display the last exception without middleware support."
  (cider--handle-err-eval-response
   (cider-nrepl-sync-request:eval
    "(clojure.stacktrace/print-cause-trace *e)")))

This should be somewhat fixed with a recent version of cider because it has a check:

 (defun cider-default-err-handler ()
  "This function determines how the error buffer is shown.
It delegates the actual error content to the eval or op handler."
  (cond ((cider-nrepl-op-supported-p "analyze-last-stacktrace")
         (cider-default-err-op-handler))
        ((cider-library-present-p "clojure.stacktrace")
         (cider-default-err-eval-handler))
        (t (cider-default-err-eval-print-handler)))) 

    With a recent cider, you will get error overlays by default because it detects no stacktrace support. 
    This currently brings another rought edge with Arcadia nrepl, because it outputs an empty string to stdout for eval. 

A current workaround would be to redefine cider-interactive-eval-handler like so:

(defun cider-interactive-eval-handler (&optional buffer place)
  "Make an interactive eval handler for BUFFER.
PLACE is used to display the evaluation result.
If non-nil, it can be the position where the evaluated sexp ends,
or it can be a list with (START END) of the evaluated region.
Update the cider-inspector buffer with the evaluation result
when `cider-auto-inspect-after-eval' is non-nil."

  (let* ((eval-buffer (current-buffer))
         (beg (car-safe place))
         (end (or (car-safe (cdr-safe place)) place))
         (beg (when beg (copy-marker beg)))
         (end (when end (copy-marker end)))
         (fringed nil)
         (res ""))
    (nrepl-make-response-handler (or buffer eval-buffer)
                                 (lambda (_buffer value)
                                   (setq res (concat res value))
                                   (cider--display-interactive-eval-result res end))
                                 (lambda (_buffer out)
                                   (cider-emit-interactive-eval-output out))
                                 (lambda (_buffer err)
                                   (cider-emit-interactive-eval-err-output err)

                                   (when (not (string-empty-p err))
                                     (when (or (not cider-show-error-buffer)
                                               (not (cider-connection-has-capability-p 'jvm-compilation-errors)))

                                       ;; Display errors as temporary overlays
                                       (let ((cider-result-use-clojure-font-lock nil))
                                         (cider--display-interactive-eval-result
                                          err end 'cider-error-overlay-face))))
                                   (cider-handle-compilation-errors err eval-buffer))
                                 (lambda (buffer)
                                   (if beg
                                       (unless fringed
                                         (cider--make-fringe-overlays-for-region beg end)
                                         (setq fringed t))
                                     (cider--make-fringe-overlay end))
                                   (when (and cider-auto-inspect-after-eval
                                              (boundp 'cider-inspector-buffer)
                                              (windowp (get-buffer-window cider-inspector-buffer 'visible)))
                                     (cider-inspect-last-result)
                                     (select-window (get-buffer-window buffer)))
                                   (when cider-eval-register
                                     (set-register cider-eval-register res))))))

clojure-emacs/cider@master...benjamin-asdf:cider:do-not-display-empty-err-overlays

[SylvianHemus]

Just wanted to thank all contributors for posting updates

[TheWitheredStriker]

My pleasure! =)

[TheWitheredStriker]

https://github.com/arcadia-unity/Arcadia/tree/ifrit

Interesting – this appears to be an active branch of Arcadia ahead of the main branch, and one of the main devs (@timsgardner) actually contributed to it as recent as last November. Does this branch have the same issues as the main one?

Has anyone tried out this branch, out of curiosity?