[notmuch] [PATCH 2/2] notmuch list: A new command to produce various lists.

[Jan Janak]

On Thu, Nov 19, 2009 at 3:41 PM, Carl Worth <cworth at cworth.org> wrote:
> On Thu, 19 Nov 2009 12:52:49 +0100, Jan Janak <jan at ryngle.com> wrote:
>> I implemented a new notmuch command that can be used to list all tags
>> present in the database:
>
> Ah, very very interesting! I'd been planning on doing something like
> this soon. And I was just thinking of "notmuch tags" as the command
> line. What other ideas do you have in mind for "notmuch list" ?

Yes, I considered "notmuch tags" too, but then I realized that we
already have "notmuch tag" and I was worried that having both tag and
tags as commands could be confusing.

I was also thinking that "notmuch list" could be extended to list
other terms than just tags, but I currently have no use-case for that.

In any case, this is just an initial proposal, I can change it to use
some other command name if you prefer that.

> One way we could possibly do "notmuch tags" is to have it accept search
> terms and then return the list of all tags from the matched messages.
> Then of course we'd need a syntax for a search term to match all
> messages, (which we want in any case).

That sounds like a good idea. If the user does not provide any search
terms then we could return all tags from the database like we do now.
If there is a search term then we could iterate through all the
messages that match it, collect their tags, sort them and present to
the user.

>> The main reason why I implemented this is because I am also working on
>> adding the tag completion feature to the Emacs mode. This is very
>> useful if you have a large collection of tags--it can save you some
>> typing and, perhaps more importantly, it minimizes the risk of having
>> typos in tag names. I'll send a patch for that later too.
>
> That will be a very nice feature to have, yes.
>
> The other reason I've wanted this is have something like a "folder view"
> that would show a list of tags and a number of messages with each tag,
> (or a number of messages with that tag and the inbox tag).

Yeah, I would want that too :-). I've already looked into this and it
seems like it should be easy to implement. At least it seems to be
easy to get the numbers from Xapian. So we would just need to come up
with a format for the list of tags with message counts, read it into
emacs and present in a buffer.

  -- Jan