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Re: truth of '()



My opinions:

1.  I don't have any problem with leaving the boolean significance of ()
    unspecified.   

2.  I am strongly in favor of retaining the fine Lisp tradition
    of treating everything other than () and #F as truth.

My concern:

    Date: Tue, 31 Jan 89 18:39:37 PST
    From: Pavel.pa@Xerox.COM
    I certainly support unspecifying the truth-value of the empty list.  Unlike
    Ken Dickey, I don't feel the need for an immediate change to specifying
    that () is true, either.  I'm perfectly willing to give implementations one
    more bounce of the report to get switched over.

I don't recall that we have any consensus for eventually declaring that
implementations -must- have distinct () and #F objects.  My understanding
is that making the boolean significance of () unspecified is to accommodate
implementations in which they are distinct, where it might be inconvenient
to arrange for () to be false.  It is not my understanding that we are
doing this as a stepping stone on the way towards defining () to be true
(which would force () to be distinct from #F).

Please note that this concern of mine has no effect on the current
discussion about ().