Re: A simple solution to "Upcoming loss of usability ..."

[Paul Eggert]

Oleh Krehel wrote:
> (font-lock-add-keywords
>   'emacs-lisp-mode
>   '(("\\(`\\)\\([a-zA-Z-0-9]+\\)\\('\\)"

The proposed approach would mishandle many cases where the things being quoted 
are not typical Lisp identifiers.  E.g.:

"Press ‘h’ for complete help; press ‘?’ repeatedly for a summary"
"Make ‘funcall/apply’ form to map SOURCE-ARGLIST to TARGET-ARGLIST...."
"... Example: ‘(ad-map-arglists '(a &rest args) '(w x y z))’ will return ..."

Also, the proposed approach won't easily generalize to diagnostics, which often 
quote non-identifiers like ‘%s’.  There's also a UI problem: ot would cause 
action-at-a-distance, because typing an apostrophe in one place in the buffer 
would visually alter a part of the line many characters away. 
(Action-at-a-distance is not a fatal objection, but it is better to avoid it 
when possible.)

Most of the advantages you mention for the proposed approach are also advantages 
of the approach in master.  With the current approach, the Emacs sources don't 
need to be changed, quotes are just as easy to input (in Electric Quote mode), 
terminal and copy-pasting work, and quotes are markup.

The main advantage of the proposed approach over the current master is that the 
source code often can still contain grave accent and apostrophe unmodified, even 
though people reading and editing the source code will see curved quotes.  To my 
mind this is more a recipe for confusion than anything else -- at least, I 
wouldn't want to inflict it on Emacs newcomers.