From: Charles Lindsey (chl@clerew.man.ac.uk)
Date: Thu Feb 05 2004 - 06:17:04 CST
In <Pine.LNX.4.53.0402041002260.17694@a.shell.peak.org> John Stanley <stanley@peak.org> writes:
>Charles Lindsey (chl@clerew.man.ac.uk):
>>Many current threading agents endeavour to
>>detect a change of subject within a thread, and move the new subthread to
>>a separate area.
>We cannot predict in what ways a software author will ignore the existing
>standards, nor in what ways he will write broken software. The fact that
>many current threading agents (I assume you mean "reading agents which
>thread articles for display", since "threading agents" don't seem to be
>defined anywhere) do so by trying make guesses when another header tells
>them explicitely is, by definition, broken behaviour, and should not be
>supported further.
But we can observe what software authors are currently doing (and have
increasingly been doing over the last few years). Users have observed that
naive threading based on the References header is a fine thing, but in
some cases what it does is not what they want. Software writers have
responded by providing the possibility (usually configurable) of modifying
the basic threading process. Moreover, it is the better regarded user
agents (e.g. Turnpike, Agent) that seem to be doing this, and their users
seem to like it. Yet you would describe them as "broken". Why?
However, for this enhanced behaviour to work correctly, this new software
has to assume that followup agents will not do "stupid" things (like
allowing two "Re:"s, or unnecessary fiddling with whitespace, or
unnecessary truncation). Note that not adding a "Re: " at all is not
"stupid", and causes no problem for those agents.
For an example of a truly "broken" agent, consider Outlook Express. Given
in the precursor:
Subject: FOO: bar
it will produce in the followup
Subject: Re: bar
:-(
-- Charles H. Lindsey ---------At Home, doing my own thing------------------------ Tel: +44 161 436 6131 Fax: +44 161 436 6133 Web: http://www.cs.man.ac.uk/~chl Email: chl@clerew.man.ac.uk Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K. PGP: 2C15F1A9 Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5