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Re: Some easy ones (?)

There are currently several declaration proposals.  The following two
forms are equivalent under all those with pervasive declarations.

(let ((a (make-a)))
  <declaration for a>
  (let ((a (refine-a a)))
    <body>))

(let* ((a (make-a))
       (a (refine-a a)))
  <declaration for a>
  <body>)

I believe that shadowing within let* is no more misunderstandable than
shadowing in general.  Almost everyone uses the same name in separate
functions for objects of a given class.  Does that confuse anyone?
Pervasive declarations are attractive because most of us use the same
convention locally.  Repeated names in let* are merely one instance of
this.

CL has thus far avoided most prescriptive style issues.  (I find it
strange that Fahlman prefers setq to let. :-)) I have no objection to
a note in the manual suggesting that some people think it's bad style
to repeat names in let*, much like it suggests that special variables
should be surrounded by *'s.  If we are opening up prescriptive style,
I'm sure Falhman, Gall and I agree that the latter is a more important
issue.  (If special variables have to be *starred*, special
declarations and all of the associated confusion goes away.)

-andy
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