New special form suggestion: LET-CONSTANT

[David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>]

Yes, CONSTANTLET would be a better name.

Proclamations don't solve Barry's concern: he doesn't want a "useless"
variable which proclomations would require.  As far as I can tell,
PROCLAIM/DEFPARAMETER is just another syntax for DEFCONSTANT and doesn't
solve anything.

On the other hand, a (DECLARE (CONSTANT XYZ)) in the declarations part
of a LET body (or of a DEFUN for &AUX) might be the way to go.

You can get what you want today, kludgily, by using MACROLET and making
the desired constants look like function calls.

I'm glad some people prefer to err on the side of naming seldom-used
constants than to wire in magic numbers into their code; numbers by
themselves don't convey much information to the casual reader.