bug#6871: Please make linum-mode per buffer, not per major mode

[Lennart Borgman]

On Wed, Aug 18, 2010 at 1:47 AM, MON KEY <monkey@sandpframing.com> wrote:
>> I think such a change is acceptable (although the motivation of
>> multi-major-mode buffers might not be that compelling, since it
>> tends to lead to the idea that most/all minor-modes should be made
>> permanent-local), but we need a proper patch for it.
>
> Thats potentially a lot of overlays to persist in buffers which:
>
> - may not always be visible
> - may be visible but don't need the linum minor-mode behaviour
>  automatically persisted
>
> Will such a change negatively impact redisplay elsewhere?
> I ask because of this comment here from linum.el:
>
> ,----
> |
> | (add-hook 'window-configuration-change-hook
> |         ;; FIXME: If the buffer is shown in N windows, this
> |         ;; will be called N times rather than once.  We should use
> |         ;; something like linum-update-window instead.
> |  'linum-update-current nil t)
> |
> `----
>
> Also, linum-mode activation already sets timers when linum-eager is
> non-nil... will these timers now persist as well on major-mode
> changes? If so how will they impact redisplay?
>
> More concretely, how many (more) permanent-locals does Lennart need in
> order to attain mumamo.el bliss?

Those things are not related.