Hi,

because it seems that notmuch does not index all headers, I've written a
simple, but quite usable tool, which goes through a maildir and generate
an output for notmuch-tag --batch according a simple rules. I've
borrowed the syntax from notmuch-tag --batch format, so it should be
very easy for any notmuch user to configure.

You can query the content of a paricular header
# tags will be applied when string is in header
+notmuch -inbox -- 'notmuch.notmuchmail.org' in 'List-Id'

or in more than one header
+notmuch -inbox -- 'notmuch.notmuchmail.org' in ('List-Id',
'X-Mailinglist')

Or use the procmail-like grep, where a whole email will be searched for
a pattern.

# procmail-like rule, the whole email is searched for a pattern
+notmuch -inbox -- 'List-Id.*notmuch.notmuchmail.org'

Note the matchin rule is a normal Python expression, so everything
Python interpreted can evaluate, should be used. I've ever wanted to
learn about those parts of a Python, so this was a nice opportunity to
learn.

https://gist.github.com/mvyskocil/5220690

Regards
Michal Vyskocil