[whatwg] Fixing undo on the Web - UndoManager and Transaction

[Ryosuke Niwa]

On Wed, Jul 27, 2011 at 8:34 PM, Alex Vincent <ajvincent at gmail.com> wrote:
>
> I'd like to take a look at this and be very closely involved in this
> specification.  About a month ago, I wrote this:
> http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-April/031191.html


Oh, yes.  I do remember your post!  I think my proposal address most of your
concerns.

Also see https://bugzilla.mozilla.org/show_bug.cgi?id=617532 - where Mozilla
> is considering their own API proposals.
>

Jonas' last proposal is very similar to the one I proposed except there are
two types of transactions in my proposal - ManualTransaction and
ManagedTransaction.  The rationale for having two types of transactions is
to let the Web app pick whether UA or script should implement undo/redo.

One use case I've envisioned is an undo popup menu, where each item of the
> undo stack has an actual label to go with it, describing the transaction.
> Then you could easily see how many items you wanted to go back!
>

My proposal addresses this use case.  See "label" property on
AbstractTransaction.

- Ryosuke