Re: How do you write input methods?

[Eli Zaretskii <eliz@gnu.org>]

> From: Filipp Gunbin <fgunbin@fastmail.fm>
> Cc: andremegafone@gmail.com,  perry@piermont.com,  emacs-devel@gnu.org
> Date: Wed, 01 Sep 2021 23:33:51 +0300
> 
> > Out of curiosity: why do you need something like that? what's the use
> > case?
> 
> It's because our LDAP server at work is a bit messy, attributes like
> "cn" and "displayname" sometimes contain first then last name, sometimes
> vice versa, sometimes in Russian, sometimes in English.  I use email
> expansion in message-mode:
> 
> --8<---------------cut here---------------start------------->8---
> (eval-after-load 'message
>   (lambda ()
>     (define-key message-mode-map (kbd "C-c TAB") #'eudc-expand-inline)))
> --8<---------------cut here---------------end--------------->8---
> 
> I want to type first letters of surname in English, press C-c TAB and
> get email autocompleted.  But the only "stable", predictable attribute
> seems to be "sn", which is unfortunately in Russian.  So I do:
> 
> --8<---------------cut here---------------start------------->8---
> (eudc-protocol-set 'eudc-inline-query-format '((sn) (email)) 'ldap)
> (advice-add #'eudc-ldap-simple-query-internal
>             :filter-args #'fg-dotemacs-ldap-advice)
> 
> (defun fg-dotemacs-ldap-advice (args)
>   (cons (mapcar (lambda (attr)
>                   (if (and (eq (car attr) 'sn)
>                            (stringp (cdr attr))
>                            (seq-every-p (lambda (c)
>                                           (eq (aref char-script-table c) 'latin))
>                                         (cdr attr)))
>                       (cons (car attr)
>                             (fg-dotemacs-translit (cdr attr) "cyrillic-translit"))
>                     attr))
>                 (car args))
>         (cdr args)))
> --8<---------------cut here---------------end--------------->8---
> 
> As ugly as it is, but it works.

So what you need is to apply the cyrillic-translit input method, just
not in an interactive context, is that true?