henry (05/18/82)
It's worth pointing out that extensible editors like Emacs really do
have disadvantages (gasp!) as well as advantages. As Steve Zimmerman
pointed out, extensibility is often used as an excuse to neglect basic
necessities, some of which turn out to be hard to do as extensions.
But there's more.
An extensibility problem which has become visible locally (in a much
less malleable editor than Emacs) is that customization has potential to
produce vast confusion in naive users, especially those who routinely
use more than one login id. It's long been accepted that hidden internal
state ("modes") is a bad thing in an editor, and extensible editors have
hidden internal state with a vengeance!
Nor does the problem vanish if one uses only a single login id, because
the behavior of an extensible editor cannot (by definition) be fully
described by printed documentation, unless said documentation discusses
the details of extension (OK for hacks, not so hot for secretaries).
Customization also makes life difficult when analyzing somebody else's
problems or prescribing solutions to same.
I don't intend blanket condemnation of extensible editors, but uncritical
worship of the concept is not necessarily justified. Extensibility is
great stuff if you have the intelligence, background, and motivation to
understand it thoroughly, and can be a curse otherwise. In an environment
with lots of naive users and few sophisticated ones, standardization of
editor behavior is a practical necessity.