[development] Use revisions to replace previews

[Karthik]

On 08/06/07, David Strauss <david at fourkitchens.com> wrote:
> With clever use of revisions, we could eliminate the preview system
> entirely from the codebase.
>
> Here's how it would work. If a user clicks Preview, it creates a new
> revision but does not mark it as the current revision. The preview seen
> is the new revision rendered. If a user clicks Save, it creates a new
> revision *and* marks it as the live one. Optionally, we could then
> delete the interim preview revisions.
>
> Another advantage to this is that a user can work on a node, preview it,
> and have their work saved. If a user comes back and edits the node with
> unsaved previews, they can choose to work from the latest preview or the
> latest public revision.

Excellent idea. IIRC, a similar approach was taken for a  "save draft"
(automatically) patch which was proposed a while back. While most of
the emphasis was on "private drafts", the idea of "public drafts" is
particularly ... juicy.