MEMBER

[Scott E. Fahlman <Fahlman@CMU-CS-C>]

Richard Stallman phoned me today with an urgent request that we
reconsider our earlier decision to have a MEMBER function that uses EQL
as the default test.  He wants us to use MEMBERP (or some other name)
for this, so that various compatibility packages can go on providing
MEMBER as a function with an EQUAL test.

At one point, several of us (including me) advocated this move, but
nobody could come up with a good name for the EQL-defualt version of
MEMBER.  I think that MEMBERP was considered at one point, but was
rejected as being inconsistent with the way we are naming the other
sequence and list functions.  (No "P"'s hanging from any of the others.)
Finally, either on the August '82 ballot or at the meeting, we decided
to go with MEMBER as the name of the EQL-defualt function.  It was
observed that any file consistently using MEMBER in the old way could be
translated automatically to (MEMBER x y :TEST #'EQUAL).  Since then, a
lot of code has been written that uses the new form of MEMBER, so there
is a cost of converting new code back to balance against the cost of
converting old code forward.

I pointed out that we had frozen the manual, but RMS felt that this
should be made a special case on the following grounds:

1. It is a trivial change that could be put into the manual and into our
implementations at the last minute.

2. This issue is so important to him and to his user community that he
would probably split with Common Lisp rather than convert to the
new-style MEMBER.

3. Stallman (and, he says, also Greenblatt) was somehow under the
impression that we had decided in August to leave MEMBER alone.
He only just realized that the manual contradicts this, and was also
taken by surprise by the "flag day" freeze -- he has not been following
the Common Lisp mailing list.

I am opposed to reopening this issue or any other issue at this point.
However, I did agree to send a query to the Common Lisp mailing list to
see whether there is significant support for this change, given
Stallman's position.  I am not in a position to assess how critical
Stallman's implementation effort is to Lisp Machine users at MIT or
what the effect might be of a split over this issue, so I didn't want to
unilaterally rule out any change in our position.  Opinions?

-- Scott