[whatwg] Random comments about UndoManager

[Ryosuke Niwa]

I'm sorry for the delay. I've updated the spec per your comment:
http://dvcs.w3.org/hg/undomanager/raw-file/tip/undomanager.html

On Thu, Apr 12, 2012 at 10:27 AM, Ryosuke Niwa <rniwa at webkit.org> wrote:

> On Thu, Apr 12, 2012 at 9:19 AM, Olli Pettay <Olli.Pettay at helsinki.fi>wrote:
>>
>> Should it be defined that <input> and <textarea> have implicit undoscope
>> by default?
>
>
> The problem is that we don't have a way of removing undo scope. We might
> need to allow undoscope=false/true.
>

I still haven't figured out this problem. On one hand, this default
behavior makes sense but we probably need a way to share undo manager
between multiple text fields. But making undoscope content attribute take a
boolean just to deal with this case is inelegant at best.

What does "destroy the corresponding UndoManager for the scope." mean?
>> If JS keeps a pointer to the manager, the object sure stays alive, and
>> if I read the draft correctly, one can use some of the methods of
>> a destroyed UndoManager.
>>
>
> Yeah, I need to define it properly. It basically means that element's
> undoManager property will return null thereafter.
>

I've introduced new concept of an undo manager being "disconnected" in
which state undo manager is immutable.

I should define what happens when you call methods on those orphaned
> methods I guess.
>

Throws INVALID_ACCESS_ERR.

- Ryosuke