Issue: TAILP-NIL (Version 5)

[Jon L White <jonl@lucid.com>]

re:    I, for one, have found that nearly every time I think LDIFF would
       suffice, the EQL test (rather than EQUAL), and its failure to take
       a test argument, has screwed me -- causing me to do what I have always
       felt is needless rewrite. I have only rarely needed TAILP and I can't
       remember if I ended up actually using it or not -- I'd suspect that
       the constraints on it make it next to useless.

This paragraph provides proof in substance of one of the reasons for
wanting to toss out TAILP, namely

   (1) the "test" questions is at least as complex as for defining
       EQUAL -- and we never did come to agreement about that;

It would only be sheer conjecture that the currently unused TAILP
would become generally useful if it were extended to take a :test
argument.   By the reasoning in your note, you don't believe we have
any way to evaluate this kind of question; you say:
    ``. . . we have no way of evaluating what it
       means for the operator to be "used a lot"''


-- JonL --