Re: Comparison of defcustom and defvar arguments

On Friday, August 21st, 2026 at 3:04 PM, [email protected] <[email protected]> wrote:

> Heime <[email protected]> writes:
> 
> > Looked at the decumentation of defcustom and defvar
> >
> > (defcustom SYMBOL STANDARD DOC &rest ARGS)
> >
> > defcustom accepts STANDARD to be an expression, and includes
> > keyword declarations such as :initualize
> >
> > (defvar SYMBOL &optional INITVALUE DOCSTRING)
> >
> > On the other hand, defvar does not seem to allow INITVALUE to be
> > an expression, and keyword declarations are not allowed.
> >
> > It seems to me that defvar is very restrictive.
> >
> 
> The definition of ‘defvar’ is complex because it can be used
> in several contexts, but it is possible to use an expression
> (which *will* be evaluated) in a ‘defvar’ expression.
> 
> Simple example:
> 
>   (defvar my-var (list (quote a)
>                        (char-to-string ?b)
>                        (cons 'c 'd)
>                        emacs-version))
> 
> M-: my-var
> 
> => (a "b" (c . d) "30.2")

I have done the following - a function returning an alist which I call
via (myalist) to set the variable value


(defun myalist ()
  "Docstring"

  (let ( (waypt orellana-waypt) )
    `( (ORLNA . ,waypt)
       (GLXKS . ,(concat basewaypt "/galaxiakos"))
       (HKDMR . ,(concat waypt "/hakudo-maru"))
       (TKYNS . ,(concat waypt "/tachyons"))
       (SVMTR . ,(concat waypt "/servomotor"))
       (AMZNS . ,(concat waypt "/amazones"))
       (GRVDR . ,(concat waypt "/groovador"))
       (KGIZA . ,(concat waypt "/groovador/kasrgiza"))
       (MTJRA . ,(concat waypt "/montejura"))) ))

(defvar this (myalist)
  orellana-fpln-dokette)

> 
> --
> The lyf so short, the craft so long to lerne.
> - Geoffrey Chaucer, The Parliament of Birds.
>