Why is there no REAL number data type?

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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.)