bug#60587: Patch for adding links to symbols' help documentation

[Gregory Heytings]

> > > No, not any longer 😊.
> >
> > Can someone tell me an easy way to make that particular diamond 
> > character display as the ASCII sequence `;-)'?
>
> (defun set-character-display (char repl)
>  (let ((c (char-from-name char)))
>    (when (and c (stringp repl))
>      (aset (or standard-display-table
>                 (setq standard-display-table (make-display-table)))
>             c
>             (vconcat
>              (mapcar
>               (lambda (char) (make-glyph-code char 'homoglyph))
>               repl))))))
>
> (set-character-display "SMILING FACE WITH SMILING EYES" ":-)")

Or, if you don't want to use the homoglyph face for such replacements:

(defun set-character-display (char repl)
  (let ((c (char-from-name char)))
    (when (and c (stringp repl))
      (aset (or standard-display-table
             (setq standard-display-table (make-display-table)))
         c (vconcat repl)))))

(set-character-display "SMILING FACE WITH SMILING EYES" ":-)")