Doom-emacs: How can one move a REPL window?

Hmm, there are a lot of moving parts here. I'm not sure what you've got C-c C-l bound to. If you aren't using the +eval/repl command to start a mode's repl, then Doom will treat the repl buffer like a common special buffer.

In that case, the two relevant variables are shackle-default-alignment and shackle-rules, which tell Emacs how to deal with windows that meet a certain criteria.

At the end of shackle-rules there are two catch-all rules:

(set! :popup 
  '("^\\*"  :regexp t :noselect t :autokill t)
  '("^ \\*" :regexp t :size 12 :noselect t :autokill t :autoclose t))))

The two problems here are :autokill t (which ensures a buffer and its associated processes are killed together) and since there is no :align specified, it resorts to shackle-default-alignment, which defaults to 'below.

So, how do we fix this?

Here are three ways:

1. Simply specify an overriding rule for your repl in particular:

   (set! :popup "*my-repl-buffer*" :align 'left :noesc t)
   

   See M-x doom/describe-setting RET :popup for details.

2. Enable the +eval-repl-mode minor mode in your repl:

   (add-hook 'inferior-python-mode-hook #'+eval-repl-mode)

   You'll find this popup rule in modules/feature/eval/config.el:

   (set! :popup
    '(:custom (lambda (b &rest _) (buffer-local-value '+eval-repl-mode b)))
    :size 16 :noesc t)
   

3. Bind C-c C-l to +eval/repl and use that instead to invoke your repl. Most modes have reasonable defaults. If it's not opening the repl you want, you can change the major-mode->repl association with the :repl setting, e.g.

   (set! :repl 'python-mode #'+python/repl)

   The function :repl wants should return a buffer containing the repl.

Hope that helps!

Oh, I forgot to mention: there is currently no way to move a live popup window (I've never needed to). That's something I'll try to fix.

That seems like all the help I needed!

To be more specific, I was actually talking about the intero REPL, started by a command called intero-repl-load. I don't know what mechanisms it uses then.

I ended up going with:

(set! :popup "^\\*intero:" :regexp t :align 'right :size 80)

in my modules/private/ptival/init.el, worked like a charm!

Thanks for taking the time to explain all this to me! I don't think I'd have figured this out on my own in any reasonable amount of time! 👍