Hi

On Mon, 21 Nov 2016, Sebastian Fischmeister <sfischme@uwaterloo.ca> wrote:
> Hi,
>
> Is there a variable defining a regex to filter harvested completions before showing them? My completions include some outdated or invalid email addresses for people and I would like to automatically remove them from the list.
>
> I didn't find something for that in notmuch-address.el, and for instance notmuch-address-matching.

There is no regex or similar, but you can filter the search used to
harvest the addresses -- see notmuch-address-internal-completion
(customisable under notmuch-send). 

You might find that putting a date limit would work; alternatively you
could tag messages from the dead addresses (eg tag:dead-address) and put
a "not tag:dead-address" in the filter field.

Best wishes

Mark