adaptive expiry? feature request?

[Eric S Fraga <e.fraga@ucl.ac.uk>]

Hello,

I used to use splitting to move all of my incoming email to various
groups.  Each group would then have different expiration policies (and
targets).  However, I hated having to switch between groups so I moved
to using scoring instead and having many of my emails (non-list ones,
say) sit in one group.  Scoring (even non-adaptive) is brilliant [1] and
I would have a hard time not using it any more!

However, this means that all of these emails are expired using the same
policy.

What I would like is to have an expiry policy that is adaptive, in the
same way as scoring is.  In fact, I would love to have an expiry time
that is a function of the score (meaning that active threads, for
instance, would not expire for quite a long time) and I guess other
message attributes.  In other words, a more general version of the
nnmail-expiry-wait-function and nnmail-fancy-expiry-targets functions
would be quite nice to have!

Is such a thing possible?  I've searched gnus variables and done a web
search of sorts but found nothing.  I think it should be possible (maybe
even straightforward?) to implement but my elisp is not good enough to
even think about doing this.

Thanks,
eric


Footnotes: 
[1]  does any other MUA have scoring?  Not that I intend to change :-)
Just curious.

-- 
: Eric S Fraga, GnuPG: 0xC89193D8FFFCF67D
: in Emacs 24.3.50.1 + Ma Gnus v0.6 + evil 1.0-dev
: BBDB version 3.02 ($Date: 2013/02/16 14:37:17 $)