On Tue, 26 Oct 2010 09:04:13 +0200 Tassilo Horn <tassilo@member.fsf.org> wrote: 

>> I think the logic should be:
>> 
>> 1) when (and (eq classification 'spam)
>> (spam-group-spam-contents-p gnus-newsgroup-name)
>> (spam-group-spam-contents-p target))
>> -> message "Sorry, can't move spam from spam group A to spam group B"

TH> Sounds right.  classification is the classification of the message,
TH> right?

>> 2) when (and (eq classification 'ham)
>> (spam-group-ham-contents-p gnus-newsgroup-name)
>> (spam-group-ham-contents-p target))
>> -> message "Sorry, can't move ham from ham group A to ham group B"

TH> Yes.

>> 3) any other case, operate normally and actually do the moves

TH> Yes.

Yes.  OK, so... untested patch follows.  It should be pretty obvious.

I have to use the test function instead of directly checking the
classification of the group, hence the slightly awkward repetition of
the test for spam and ham testing.

Ted