[Users] How to write this plugin?

[Tom Horsley]

I'm wondering how much work it would be to write a new plugin,
possibly named "Trollkiller".

The idea would be to mark either mail from specific users
as troll messages, or just a particular message as a troll.

Then the plugin would remember (possibly in a sqlite
database) the message IDs of the troll messages,
search for them in incoming References: headers
and add new message IDs to the troll list.

The goal: to utterly eradicate all threads following up
a troll. Either make them be silently deleted
or send them to a troll cage inbox.

If sufficient time elapses with no more follow ups
to a troll thread, the database could be cleaned of those
message IDs.

"Please don't feed the trolls" works only when everyone
follows that philosophy, but since virtually no one follows
that rule, this plugin could simulate a world in which
the rule was being followed :-).