How to set calendar-date-style in init?

How to set calendar-date-style in init?

[Pankaj Jangid]

I have tried following options in my init file, but none of them seem to
be working. I have tried with and without /lexical-mode:t/.

I have tried following options. What am I doing wrong here?

--8<---------------cut here---------------start------------->8---
;; option-1
;;(declare-function calendar-set-date-style "calendar.el")
;;(calendar-set-date-style 'european)

;; option-2
;; (custom-set-variables
;;  '(calendar-date-style 'european))

;; option-3
;; (defvar calendar-date-style)
;; (setq calendar-date-style 'european)

;; option-4
(eval-when-compile (require 'calendar))
(setq calendar-date-style 'european)
--8<---------------cut here---------------end--------------->8---

Re: How to set calendar-date-style in init?

[Michael Heerdegen]

Pankaj Jangid <pankaj@codeisgreat.org> writes:

> I have tried following options. What am I doing wrong here?
>
> ;; option-1
> ;;(declare-function calendar-set-date-style "calendar.el")
> ;;(calendar-set-date-style 'european)

Since `calendar-set-date-style' is not autoloaded, you need to
explicitly (require 'calendar).  The `declare-function' call only
tells the byte compiler that it should not barf, but you are responsible
to ensure that the function is known at load time.

> ;; option-2
> ;; (custom-set-variables
> ;;  '(calendar-date-style 'european))

I think this will also only work if you require 'calendar.

> ;; option-3
> ;; (defvar calendar-date-style)
> ;; (setq calendar-date-style 'european)

`defvar' without an argument makes the variable only special in the
loaded buffer.  (defvar calendar-date-style 'european) should work
(though calling `calendar-set-date-style' will set even more variables).

> ;; option-4
> (eval-when-compile (require 'calendar))
> (setq calendar-date-style 'european)

requiring calendar only at compile time will not make the variable
special when your file is loaded.

Ok, finally, which option should you use?  Most of the time people
choose option-5, using `with-eval-after-load'.


Regards,

Michael.