HACKING in sup-0.0.8 vs HACKING in sup-0.1

@@ -2,49 +2,19 @@
 -------------------
 Invoke it like this:
 
 ruby -I lib -w bin/sup
 
+You'll have to install all gems mentioned in the Rakefile (look for the line
+setting p.extra_deps). If you're on a Debian or Debian-based system (e.g.
+Ubuntu), you'll have to make sure you have a complete Ruby installation,
+especially libssl-ruby.
+
 Coding standards
 ----------------
 
 - Don't wrap code unless it really benefits from it. The days of
   80-column displays are long over. But do wrap comments and other
   text at whatever Emacs meta-Q does.
-- Use as few parentheses as possible.
+- I like poetry mode.
 - Use {} for one-liner blocks and do/end for multi-line blocks.
-
-How messages are updated in the index
--------------------------------------
-
-Ferret doesn't have any concept of updating; to change message state
-it must be deleted then re-added to the index.
-
-Thus there are a couple situations where we'll have a message to be
-"added", but it already exists in the index, and we need to decide
-which parts of which version to keep:
-
-1. The user has changed the state of the message, e.g. read it or
-   added a user label. In this case we want to use the state of the
-   version in memory, but keep everything else on disk.
-
-   This is the behavior of Index#update_message
-
-2. We've received a new copy of the message. Crucially, this can
-   happen for two different reasons:
-
-   a. The message was sent to a mailing list to which the user is
-      subscribed, and we're now getting that message back, possibly
-      with altered content (subject mangling, signature adding, etc.)
-
-   b. The user has moved the message between sources. E.g. if the
-      primary inbox has a quota, and other sources are on local,
-      quota-less disk, the user may regularly move messages from the
-      inbox to the sources on disk.
-
-   In both of these cases, the solution is to keep the state from the
-   index, but use the new message contents.
-
-   This is the behavior of Index#update_or_add_message, which can be
-   also be called for new message.
-