bug#74511: 31.0.50; `dictionary-search-interface' overrides the user's customization of `dictionary-read-word-function'

[Eli Zaretskii <eliz@gnu.org>]

> From: Steven Allen <steven@stebalien.com>
> Cc: 74511@debbugs.gnu.org
> Date: Sun, 24 Nov 2024 12:36:00 -0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> Date: Sun, 24 Nov 2024 10:56:08 -0800
> >> From:  Steven Allen via "Bug reports for GNU Emacs,
> >>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> >> 
> >> 
> >> If the user customizes `dictionary-read-word-function' then loads the
> >> dictionary package, the value of `dictionary-read-word-function' will be
> >> overridden when `dictionary-search-interface' is loaded. To reproduce:
> >> 
> >> 1. Run emacs with `emacs -Q`.
> >> 2. Open a scratch buffer and evaluate the following:
> >> 
> >>     (setopt dictionary-read-word-function 'dictionary-completing-read-word)
> >>     (require 'dictionary)
> >>     (message "%S" dictionary-read-word-function)
> >> 
> >> I'd expect `dictionary-read-word-function' to be
> >> `dictionary-completing-read-word' but instead it gets reset back to the
> >> default, `dictionary-read-dictionary-default'. I can work around this by
> >> calling `setopt' after loading the `dictionary' package, but ideally
> >> that wouldn't be necessary.
> >
> > You are supposed to customize dictionary-search-interface if you want
> > this mode of operation.
> 
> In addition to dictionary-search-interface, there are three separately
> customizable variables:
> 
> - dictionary-display-definition-function
> - dictionary-read-word-function
> - dictionary-read-dictionary-function
> 
> I'd expect dictionary-search-interface to override the defaults for
> these variables, but I wouldn't expect it to completely clobber any user
> customizations of said variables.
> 
> If these variables cannot be customized, I'd expect them to be "defvar"
> not "defcustom". Although that would be rather unfortunate because,
> while I want to enable minibuffer completion for words/dictionaries, I'd
> also like to use the real dictionary mode (not the help buffer).
> 
> Adding ":initialize 'custom-initialize-changed" to
> dictionary-search-interface would make it possible to specify either
> dictionary-search-interface or any of the other variables (but not both
> at the same time).

Eshel, would you please look into this?  IMO, we should at least
improve the documentation to clarify these subtleties.  Bonus points
for allowing users to customize the other options without clobbering
them when the package is loaded or dictionary-search-interface is
customized.

Thanks.