Re: A little help from my friends

[Nathan Williams <nwilliams@primeon.com>]

Kai.Grossjohann@CS.Uni-Dortmund.DE writes:

> One possible behavior which IMAP could exhibit (but probably doesn't)
> is that entering the `foo' group (folder) means you also see the
> messages from the `foo.bar' group.
> 
> Is the hierarchy more than just a naming convention?

        A little bit. It's a naming convention understood by the
server, and certain operations (such as LIST) can use the special
wildcard character '%' to avoid listing subfolders. That is, with a
seperator of '/' and the following folders on the server:

top-1
top-2/sub-1
top-2/sub-2
top-2/sub-2/sub-1
top-3

the command 'LIST "" "*"' would return all of them, while 'LIST ""
"%"' would only return top-1, top-2, and top-3. So if you have a
client which wants to dynamically expand and contract sub-hierarchies
in a tree of mailboxes, it can do so with help from the server and
avoid some unnecessary traversal. If you set up mailboxes with your
own separator that the server doesn't know about, then you lose that
(admittedly not huge) benefit. 
        
        Also, since mailboxes can have the \Noselect attribute, it is
possible to have top-2 by itself as part of the listable hierarchy
without it having to be an actual group.

        - Nathan