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

[Oleh Krehel]

Hi all,

It seems that even though many conservative people disagree, the
"experiment" isn't going away.

So I'm proposing the following change that could satisfy both Paul and
the conservatives (myself included):

(font-lock-add-keywords
 'emacs-lisp-mode
 '(("\\(`\\)\\([a-zA-Z-0-9]+\\)\\('\\)"
    (0
     (compose-region
      (match-beginning 1)
      (match-end 1)
      "‘"))
    (0
     (compose-region
      (match-beginning 3)
      (match-end 3)
      "’")))))

The above code can also be made part of `prettify-symbols-mode', and
some customization can be added to turn things on or off. The above code
is only a rough draft, it may not be optimal, which the experts could
quickly fix. But it works for all Emacs versions installed on my system.

The advantages of the above approach:

1. Paul's students get to see the pretty quotes.

2. The Emacs sources need not be changed, no new syntax definitions need
to be introduced.

3. The pretty quotes are easy to input for Paul's students: they're
right there on the standard issue keyboard, available with zero modifier
keys: even the Shift modifier isn't necessary.

4. Zero problems in the terminal and with copy pasting: that part of
`prettify-symbols-mode' could be just disabled for terminals that don't
support Unicode. In addition, I can actually see the Unicode quotes fine
in GNOME Terminal. They look garbled on a TTY, but again: the minor mode
can be enabled/disabled conditionally.

5. The quotes stay what they are: markup, as they were intended to be.
The markup can be rendered in many different ways, including as Unicode
quotes, if the user prefers.

regards,
Oleh