Re: nnir, gnus-goto-article and such

[Ted Zlatanov <tzz@lifelogs.com>]

On Thu, 29 Sep 2011 10:40:50 -0400 Dave Abrahams <dave@boostpro.com> wrote: 

DA> general usage of the registry, which only happens in a very few
DA> circumstances even though the kind of queries the registry can
DA> answer are all over the place.

It's a fairly new component and I haven't pushed it hard on anyone.

>> Users should be able to use every aspect of Gnus without calling
>> `gnus-registru-initialize'.  The memory usage of the gnus-registry, if
>> we enabled it by default, would be unpleasant for many of our users on
>> older or less capable machines.  Thus any general Gnus functionality
>> should not depend on the gnus-registry's availability.

DA> Well, here's an example of a missing generalization then.  The registry
DA> provides a general interface for looking up (information about) articles
DA> based on their message IDs.  However, there's only one of them, and it's
DA> persistent.  nnir would only need a small, special-purpose registry for
DA> each of its groups.  Or, maybe better, one registry could be refcounted
DA> and just discarded when you leave the last nnir group if you haven't
DA> initialized the registry in the meantime.  It wouldn't grow if nobody
DA> was putting things in it.

That's not hard to do using registry.el, which is intended to be a
general-purpose storage facility with or without persistent.  But I
unfortunately don't have the time or need to do what you suggest.

>> Furthermore the gnus-registry should be treated as a lossy cache.  If
>> you find something useful, great.  But don't rely on it.  That attitude
>> lets us expire it more aggressively.  There are "precious" properties
>> you can set, so for instance the registry marks are not lost, but from
>> our side we can't expect that.

DA> Sorry, don't know what you mean by "our side."  You can't make things
DA> precious programmatically?

Sure, but choose not to.  I think it should be entirely up to the user
what he wants to keep around.

Ted