Re: Emacs's handling of line numbers [from bug#5042]

[Eli Zaretskii]

> From: Juanma Barranquero <address@hidden>
> Date: Sun, 18 Apr 2010 05:49:54 +0200
> Cc: address@hidden, address@hidden, address@hidden
> 
> if I'm reading an Info node, my narrowing/widening
> shouldn't interfere with the use of narrowing by Info-mode, because
> that's just an artifact of its implementation.

If that's the problem, we could disable narrowing/widening in Info
mode.  (I'm not saying we should, but if we decided to do so, it would
be IMO a better solution than a whole new infrastructure with two
kinds of restrictions.)

> Being able to do M-x
> widen in an Info node and seeing the whole buffer is IMO a "bug"
> because it destroys the abstraction.

Actually, it happens to be a feature (more accurately, a basis for a
feature), both in Info and in Rmail.

> On the same vein, if I were implementing a package that needed to
> show/hide portions of the buffer, I would likely prefer the user not
> to be able to break the abstraction just by accidentally doing M-x
> widen.

But you will never be able to disallow widening completely, because
the primitives are not going to go away, and there's nothing to
prevent a motivated individual from invoking them, even if they are
non-interactive.

IOW, I don't see how the suggested duplicity will solve enough of the
problem to justify the added complexity.  (For that matter, I don't
see the problem, either -- see my other mail in this thread.)