Why article numbers?

[kai.grossjohann@uni-duisburg.de (Kai Großjohann)]

Now that I'm thinking about it again, maybe it is possible to migrate
all of Gnus away from article numbers as identifiers, towards some
opaque data type?  That would facilitate some new features (such as
offline message moving).

One could implement a data type for the article "numbers", then use
that data type throughout.  Then one could change the implementation
of that data type to something incompatible with article numbers to
ensure that it is used everywhere.  Then various backends could use
whatever they liked.

It would destroy using ranges.  Are ranges important in Gnus?  How
could bad side effects be avoided on the transition to, say, message
ids?

Maybe the most difficult part is the "marked as read" thing: how do
you use message ids to store the fact that articles 1 through 50,000,
say, have been read by the user or disappeared altogether?  If you
store the first message id that has been read, and then that message
is moved to another group or canceled...  Whee.

Thoughts?
-- 
A turnip curses Elvis