Re: Gnus always loads cl

[Katsumi Yamaoka <yamaoka@jpl.org>]

>>>>> In <87adlgb3w7.fsf@crybaby.cs.uni-dortmund.de>
>>>>>	Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Großjohann) wrote:

> (eval-and-compile
>   (when (= emacs-major-version 20)
>     ;; gethash, hash-table-count, make-hash-table, mapc
>     (require 'cl)
>     (defalias 'puthash 'cl-puthash)))

Kai> I'm not so happy with this.  It is better to just check whether the
Kai> functions are defined, I think.  Maybe something like this?

Kai> (unless (fboundp 'puthash)
Kai>   (require 'cl)
Kai>   (defalias 'puthash 'cl-puthash))

It is correct if you mean there might be puthash provided by
other than cl even if Emacs 20 is running.  And that form will
also load the other cl run-time functions, gethash,
hash-table-count, etc., which are required by spam-stat.el.
Probably, it should strictly be made as follows:

(unless (and (fboundp 'gethash) (fboundp 'hash-table-count)
	     (fboundp 'make-hash-table) (fboundp 'mapc)
	     (fboundp 'puthash))
  (require 'cl)
  (unless (fboundp 'puthash)
    (defalias 'puthash 'cl-puthash)))

However, if such a thing is required, my will inclines to
forsake Emacs 20 users.  Do you have any other ideas?

Kai> In principle, it is also bad to do the defalias, but maybe in this
Kai> case `puthash' is sufficiently standard so that the defalias is good
Kai> anyway.

I think I understand your opinion.

Kai> Hmmm...  But isn't puthash defined as a macro in cl-macs.el or cl.el,
Kai> even in Emacs 20?  So I'm surprised that you need the defalias.  Or
Kai> maybe only gethash etc are macros, and the macro is missing for
Kai> puthash?

All cl run-time functions used by spam-stat.el are the normal
functions in Emacs 20.  I was also surprised that puthash isn't
available in Emacs 20.  gethash is an alias to cl-gethash in
cl-extra.el, but puthash isn't.

Kai> In this case, please add a comment saying "alias puthash is
Kai> missing from Emacs 20 cl.el" or something like that.

I agree.  To be sure, it is required.
-- 
Katsumi Yamaoka <yamaoka@jpl.org>