tri-state classification

[Dave Lovelace]

Pavel Kankovsky wrote, in part:
> 
> On Tue, 26 Oct 2004, David Relson wrote:
> 
> > RELEASE.NOTES-0.93 covers the subject.  I've included a copy at the end
> > of this message.  It's also mentioned in the NEWS-0.9x and CHANGES-0.9x
> > and will be prominently mentioned in the announcement.
> 
> Yes, sure. But we all know how much attention people pay to the
> documentation. :)
> 
I've had experience with this problem, as the user, in the past, & I'll
offer myself as an example for this case.  We're running bogofilter
version 0.17.1 - quite old, but we haven't had any reason to upgrade.
There have been a lot of really major changes.  If we ever have to upgrade,
I'll have to look through a potentially HUGE RELEASE.NOTES document, 
Which changes are ones that will require me to change config files,
user scripts, etc.?  Experience says that it will be impossible to tell
from the RELEASE.NOTES.  I haven't looked at bogofilter's document
recently; I'm going by experience with some other packages here.
I've had to try to find what's important in 80- or 90-page documents,
organized purely chronologically, which assume that the user understands
all the ins & outs of the program - usually not the case.

I don't know a good solution; I'm just saying "It's in the doc" is not
necessarily much reassurance.

<...>

> IMHO, there are 3 basic options (in the order of increasing implementation
> complexity and decreasing user inconvenience):
> 
> 1. print a warning unconditionally, and go on, (this option was not
>    explicitly mentioned in the original proposal)
> 
> 2. test whether the sematics of the *given* configuration file,
>    taking its *actual* settings into account, would change, print a
>    warning if necessary, and go on,
> 
> 3. try emulating 1.2.3 (and perhaps print a warning as well).
> 
Um.  Print a warning where?  I, for instance, am running bogofilter from
procmail, simply testing the (two-state) exit value.  Other users here
have procmail adding a Spamicity header, which pegasus later looks for.
Where is the warning going to go?

Again, I don't know a better idea.

-- 
- Dave Lovelace
  dave at firstcomp dot b i z
  davel at cyberspace dot org