[whatwg] Random comments about UndoManager

[Ryosuke Niwa]

On Tue, May 29, 2012 at 11:27 PM, Ryosuke Niwa <rniwa at webkit.org> wrote:

> 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.
>

I talked about this about with Ojan and in person and he came up with
undoscope=shared to indicate that the undo manager of the text field should
be shared.  Alternatively, we can have explicit "undoscope=false" to mean
the undo scope is not set, thereby sharing with its parent element.

I haven't heard anything from Microsoft yet but it appears that WebKit can
change its behavior to have one undo manager per text field as far as I've
consulted with various WebKit contributors. If anything, we can leave the
default implementation dependent and let scripts figure it out by
inspecting the undoScope attribute on input/textarea elements.

- Ryosuke