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Re: Types of Functions

    Date: Wed, 2 Jul 1986  19:56 EDT
    From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
    To:   James Rice <Rice@SUMEX-AIM.ARPA>
    Subject: Types of Functions
    In-Reply-To: Msg of 2 Jul 1986  13:55-EDT from James Rice <Rice at SUMEX-AIM.ARPA>
    Message-ID: <FAHLMAN.12219579841.BABYL@C.CS.CMU.EDU>
	Why is it that in CLtL (p 76) Functionp is the only type
	predicate which is not specified to be equivalent to
	(typep foo 'function)?
    Good question.  I don't remember, and can't think of any good reason for
    this omission.  Does anyone else remember what's going on here?  It is
    too glaringly different from the neighboring descriptions to be an
    inadvertent omission.  Maybe it is just the result of the confusion
    about what we mean by function, which got tightened up a bit after this
    section was written and needs to be tightened up still more.  Once that
    is done, I see no reason for Functionp not to be equivalent to Typep of
    -- Scott

(typep foo 'function) causes an error to be signalled according to
page 47.  Perhaps that is why functionp is not defined in terms of it?

-- Nick