EIEIO accessing class slots

[pillule]

Hi

How can I accede to the initarg of an eieio class ?

Let's say I have a class as :

(defclass moirai-dired-side ()
  ((display-alist
    :initarg :display-alist
    :initform '((moirai-dired-p)
                (display-buffer--in-dired-side-window)
                (slot . 0) (side . left) (select . t)
                (preserve-size (t . t)) (window-width . 35)
                (window-parameters . ((no-other-window . t)
                                      (no-delete-other-windows . t))))
    :custom (custom-variable-type 'display-buffer-alist)
    :documentation
    "Alist of conditionals actions for `display-buffer',
It is the same format that `display-buffer-alist'.")))


Now I can create instances with

(setf morai-dired-side-left (moirai-dired-side))

And so far manipulating the object will work fine,
but if we go back to the class itself ...

;; apparently this is not an eieio-class ?!
(eieio--class-p 'morai-dired-side)
;; => nil

;; but I can anyway access its slots
(eieio-class-slots 'moirai-dired-side)
;; => (#s(cl-slot-descriptor display-alist '((moirai-dired-p) 
(display-buffer--in-dired-side-window) (slot . 0) (side . left) (select . t) 
(preserve-size (t . t)) (window-width . 35) (window-parameters (no-other-window 
. t) (no-delete-other-windows . t))) t ((:documentation . "Alist of 
conditionals actions for `display-buffer',
It is the same format that `display-buffer-alist'.") (:custom 
custom-variable-type 'display-buffer-alist) (:group default))))

;; the issue is I have no idea of how to get them individually
(eieio--class-slot-initarg 'moirai-dired-side :display-alist)
;; ! Wrong type argument: eieio--class, moirai-dired-side, class


Am I missing something ? I seen a bug report from 2015 at this subject 
(#bug19552) but it doesn't help.

As a side note the eieio manual is outdated, it references 'class-slot-initarg',
while it is now 'eieio--class-slot-initarg'.

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