[tlug] Re: Following Threads . . . what are they after all?

["Stephen J. Turnbull" <stephen@example.com>]

Michal Hajek writes:

 > > What do you mean by ""usage pa[t]tern"? 
 > 
 > I was imagining there might be some functionality to directly jump to a
 > message in a thread using the information from currently viewed/edited
 > one. 

In the (Emacs-based) MUA Gnus, things that look like addresses are
highlighted and clickable.  If it's in From, To, Cc, etc, it is
considered a mailto URL, and clicking on it will drop you into the
message composer with a reply to that mailbox.

If it's in Reply-To or References, it is considered a message ID and
clicking on it will jump to the corresponding message, if (a) it is in
one of your message folders or (b) it can be retrieved from your
netnews server (optional, since netlags can be long).

Gnus also provides a `parent-message' command, typically bound to the
"^" key, which goes to the previous message in the thread, skipping
back over different sub threads.  Eg.  Suppose you are at Z in this
thread, where A is the root and each message is a reply to the nearest
previous message with less indentation:

A
  B
    C
  D             ; the second reply to A
    E
      F
        G
        H       ; the second reply to F
  Z

Then from Z `previous-message' will take you to H, but that's usually
not very useful.  `parent-message' takes you directly to A (and will
also search your newserver if that feature is enabled).

 > I thought threads are used to mark line of thought. And I broke that
 > previous thread since I saw my reply as starting a _new_ line of
 > thought. 

No.  Subjects mark the topic (line of thought).  Threads provide
context.  Consider somebody who is trying to be good about trimming,
and snips too much.  Then a parent-message command using the thread
can give you the missing context very quickly.

Thus a thread is not a line, it's a tree.  Unfortunately, there is no
provision for making it a DAG although convergent subthreads are
encountered frequently, especially in the form of two complementary
replies to the same message.