bug#13646: mode-specific and file-regexp-specific settings

[Didier Verna <didier@didierverna.net>]

Stefan Monnier <monnier@IRO.UMontreal.CA> wrote:

> I think the idea is good, but I don't think the solution should be
> specific to whitespace.el.

  A general solution would be nice of course (but this is frightening;
  see below). I'm not familiar enough with the dir-local functionality
  (XEmacs doesn't have that) to comment on it though.

> Also, we should introduce a way to set variables to a value that is
> mode-dependent.  Maybe something like
>
>   (setq-modes whitespace-style
>      (foo-mode 'face)
>      (bar-mode 'trailing)
>      (t 'tab-mark))

  This looks a bit hackish. If you're going down that road and want to
  be that general, why stop here ? Someday, someone will want
  window-specific values and what not and you'll end up with tons of
  setq variants. And then, you're gonna wish you had specifiers in the
  first place (and /that/ is frightening) :-)

> Which could turn into something akin to
>
>   (setq-default whitespace-style 'tab-mark)
>   (add-hook 'bar-mode-hook (lambda () (setq-local whitespace-style 'trailing)))
>   (add-hook 'foo-mode-hook (lambda () (setq-local whitespace-style 'face)))

    Question: if you have both the above and dir-local settings, which
    ones take precedence (I hope the dir-local ones) ?

-- 
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