Re: [PATCH] emacs: add global tag history

[David Bremner <david@tethera.net>]

Carl Worth <cworth@cworth.org> writes:

> On Wed, Jan 26 2022, inwit wrote:
>>> Even that will not be perfect (since the messages matching the query
>>> could change behind emacs back), but close enough for most interactive
>>> use, maybe?
>>
>> I was thinking about saving the IDs of the messages affected by the 
>> change, but I still don't know how would I go about that or if it's 
>> sensible.
>
> One could imagine a history that would enable a conventional undo stack
> for a notmuch interface. The trick with making that usable would be the
> need to refresh views to make what was undone evident, (and the fact
> that some of the operations could be large/slow).
>
> All of those issues kept me from pursuing the idea in early days of
> coding up the emacs notmuch UI. But someone could certainly explore the
> implementation further if desired.

One thing that has changed since those early days is that we now have
lastmod (see notmuch-search-terms(7)): queries, but that is still not
atomic. I guess it might not be too hard to have notmuch tag output
output the correct lastmod value. Then we could store that as shorthand
for a set of messages.

d