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Why is there no REAL number data type?

    Date: Mon, 29 Jan 90 14:18:15 CST
    From: "RDP%ALAN.kahuna.decnet.lockheed.com"%ALAN.kahuna.DECNET.LOCKHEED.COM@Warbucks.AI.SRI.COM

    Received: from THOMAS.kahuna.decnet.lockheed.com by ALAN.kahuna.decnet.lockheed.com via CHAOS with CHAOS-MAIL id 19020; 29 Jan 90 11:58:06 PST
    Date: Mon, 29 Jan 90 11:57 PST
    From: Robert D. Pfeiffer <RDP@ALAN.kahuna.decnet.lockheed.com>
    Subject: Why is there no REAL number data type?
    To: SLUG@ALAN.kahuna.decnet.lockheed.com
    Message-ID: <19900129195748.6.RDP@THOMAS.kahuna.decnet.lockheed.com>

    (This question has occurred to me a few times over the last couple of
    years so I thought that I'd finally ask it.)

    Can anyone tell me why the type REAL isn't defined in Common Lisp (nor
    SCL)?  It would seem like a good and useful type to have.  It should
    be a direct supertype of RATIONAL and FLOAT and a direct subtype of
    NUMBER.  It would provide a convenient way to specify a noncomplex number
    (RATIONAL, for example, takes an argument of this type).

    Comments, anyone?  (Particularly you CL language theorists.)

ANSI Common Lisp will have the REAL type.  When we were adding the
argument types to the language spec we noticed the type (AND NUMBER (NOT
COMPLEX)) coming up quite often and realized how stupid it was not to
have a name for that type.