RE: [External] : Re: [PATCH v3] Allow applying filters to summary consecutively

[Drew Adams <drew.adams@oracle.com>]

Not really following this thread, but ... HTH.

I think what's being described is what I call 
"progressive" filtering/narrowing.

Whether or not other operations are carried
out between two successive filtering
operations is, IMO, immaterial. "Consecutive"
application of filters doesn't imply absence
of other operations between filtering
operations (but someone might think that).
"Successive" is better than "consecutive" in
this regard: "consecutive" is "successive
without a break".

How filtering is done (pattern matching,
predicate application, something else) is
also immaterial.  You're just narrowing a
set of <whatevers> in some way, IIUC.

For Icicles "progressive completion", which
is the same kind of thing, I also describe
it as similar to `grep' chaining/cascading,
which involves piping the output of one
`grep' to the next one (possibly after
other operations that also emit a stream of
chars).  Not all Emacs users are programmers,
but many are familiar with piping `grep'.

And I do describe it as set intersection, as
well as ANDing (Boolean multiplication).
Key sequences for it include the use of key
`*' (or `&' when a predicate is used instead
of a pattern).  (For set union / ORing, keys 
include the use of `+', for Boolean addition.)

I don't think "intersect(ion)" is hard for
Emacs users (including nonprogrammers) to 
understand.  It's not only "mathematical",
and it's not esoteric.

Just one opinion.  HTH.