I've received several positive replies to my request, so the work is
going ahead. It has been suggested that, instead of initializing all the
counters to zero at the start of each filtering operation, some of them
(the first 5, say) be left containing the values they were set to by the
system filter. Then a system filter could do some scoring, and users'
filters could take decisions based on those scores.
[A user who wants to reset a counter to zero can always do so by a
command such as
add -$n3 to n3
for example. (I'd better make sure that works when n3 contains a
negative number, or else invent a "subtract" command.)]
--
Philip Hazel University Computing Service,
ph10@??? New Museums Site, Cambridge CB2 3QG,
P.Hazel@??? England. Phone: +44 1223 334714
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