Re: EIEIO: how to validate a new instance?

Re: EIEIO: how to validate a new instance?

[David Engster]

Raffaele Ricciardi writes:
> but I can't find the proper incantation to make it work (I even
> managed to make Emacs crash).

Even if your initial problem is solved, please define "crash". If you
managed to provoke a segmentation fault through Emacs Lisp, then this is
a bug.

-David

EIEIO: how to validate a new instance?

[Raffaele Ricciardi]

Hello everyone,

I need to create a new EIEIO object, but not all values are acceptable as
initargs.  My understanding is that I should use initialize-instance for 
checks,
but I can't find the proper incantation to make it work (I even managed 
to make
Emacs crash).

Here is a sample code:

(require 'eieio)

(defclass my-class ()
   ((x :initarg :x
	   :type string )))

So far, so good.  I can instantiate my class:

(setq ^c (my-class "my-class" :x "x"))

Here is one of my attempts at initialize-instance:

(defun initialize-instance ((^c my-class) ^args) nil)

It doesn't work: now I can't instantiate my class anymore:

(setq ^c (my-class "my-class" :x "x"))

Fails with:

 > Debugger entered--Lisp error: (invalid-function (lambda ((^y 
my-class) ^args)
nil))
 > initialize-instance([object my-class "my-class" unbound] (:x "x")) Any
help?  Thank you.

Re: EIEIO: how to validate a new instance?

[Raffaele Ricciardi]

Ouch!  I had to define initialize-instance with defmethod, not defun.

Thank you all for the attention.