Re: How to convert an arbitrary string into a filename

[Eli Zaretskii]

> Date: Thu, 27 Apr 2023 07:52:55 +0300
> From: Jean Louis <bugs@gnu.support>
> Cc: help-gnu-emacs@gnu.org
> 
> * Eli Zaretskii <eliz@gnu.org> [2023-04-26 16:09]:
> > If you need to convert an accented character to its base character
> > (i.e. "remove" the accent), Emacs has much more general facilities:
> > 
> >   (require 'ucs-normalize)
> >   (substring (ucs-normalize-NFKD-string "Ć") 0 1)
> >    => "C"
> 
> Alright, then like this:
> 
> (defun string-slug (s &optional random)
>   "Return slug for Website Revision System by using string S.
> 
> RANDOM number may be added on the end."
>   (let* ((random (or random nil))
>        ;; (case-fold-search t)
>          (s (replace-regexp-in-string "[^[:word:]]" " " s))
>          (s (replace-regexp-in-string " +" " " s))
>        (s (substring (ucs-normalize-NFKD-string s) 0 1))
>          (s (replace-regexp-in-string "^[[:space:]]+" "" s))
>          (s (replace-regexp-in-string "[[:space:]]+$" "" s))
>          (s (replace-regexp-in-string " " "-" s))
>        (s (if random (concat s "-" (number-to-string (random-number))) s)))
>     s))
> 
> (string-slug " OK, here, üößčć") ➜ ""
> 
> It doesn't give good result.

Of course.  Because you didn't understand how to use
ucs-normalize-NFKD-string for your purposes.  Please read its doc
string, and try to play with it, starting from the example I've shown.