DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma;
	h=mime-version:sender:in-reply-to:references:date
	:x-google-sender-auth:message-id:subject:from:to:cc:content-type
	:content-transfer-encoding;
	b=UYZW+S7ftVaens/23AXhteJ/cNvI14OwV0R4aCqXqRsM0ydcWS4XiYp5KAl9R0W9+N
	CjA186+2OKtE/9J9ixeXA1A2kOR4r7vtt3+B99Wjrto7dCUTiiF/y0evn8vvB8wQRtG9
	/kMKsPObjj1swIypXkmBltEsEKZSdlhJQc+Mc=
MIME-Version: 1.0
Sender: amdragon@gmail.com
In-Reply-To: <871uznqeox.fsf@tredergarh.home.box>
References: <87fwoath2s.fsf@gilead.home.box>
	<BANLkTinKS5LbQsZuK8HyCzj+Lo4xqa2Sfg@mail.gmail.com>
	<871uznqeox.fsf@tredergarh.home.box>
Date: Wed, 25 May 2011 10:44:51 -0400
Message-ID: <BANLkTin0+O=mubHF7JNpw4u3DQDQJQ5zbw@mail.gmail.com>
Subject: Re: [PATCH] emacs: Make the queries used in the all-tags section
From: Austin Clements <amdragon@mit.edu>
To: Daniel Schoepe <daniel.schoepe@googlemail.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Cc: notmuch@notmuchmail.org
Precedence: list

On Wed, May 25, 2011 at 6:04 AM, Daniel Schoepe
<daniel.schoepe@googlemail.com> wrote:
> On Wed, 25 May 2011 00:10:43 -0400, Austin Clements <amdragon@mit.edu> wr=
ote:
>> Out of curiosity, what use cases do you envision for this? =A0So far
>> I've only heard two, both of which seem like great ideas, but neither
>> of which require such a heavy-handed solution: displaying unread
>> counts for tags rather than total counts, and hiding unused tags.
>
> Another thing I use this for, is to hide messages/threads with a
> "killed"-tag.

Ah, interesting.

> I think a sensible compromise would be to allow either a function or a
> string that is appended (which people could set to "and tag:unread") for
> the proposed configuration variable and additionally to add a
> variable that lists tags that should be hidden (which would also be
> easily modifiable in M-x customize).

In principle, I completely agree, but the little parser in my head
screams "parse error!  parse error!" when I feed it "and tag:unread"
and that bothers me.

May I suggest a slightly different way of looking at this that will
quell my inner parser?  Instead of configuring a weird "query
fragment" like "and tag:unread" to be string-concatenated with the tag
query, configure a *filter* query like merely "tag:unread" that
narrows down what you'd like to be counted within the scope of a tag.
The implementations are hardly different---simply generate the query
"tag:<tag> and ( <filter> )"---but a filter is a well-formed query,
not some string fragment.  Furthermore, the user can't get bitten by
precedence and wind up with a query that counts messages that don't
even have that tag.