I'm confused about an eval-when in cl-info.lisp with GCL

I don't understand it either, but it seems to me
that re-defining while  (isn't it standard in CL?) is
a bad idea if your re-definition is identical to
the original,  and any conditionalization for the
"new implementation of lisp"  (NIL) version of Maxima
probably should just be removed. NIL was written for
the VAX computer only, and it was never operational
there.  The NIL conditionalizations were, I suspect, put in the
source code to make it harder for people to understand
the code that was released to the Dept. of Energy
by MIT.

 Since NIL never had a garbage collector, it could not
really be used for anything serious.

RJF



James Amundson wrote:

>I'm confused about some behavior I see in cl-info.lisp under GCL.
>cl-info.lisp contains the following snippet:
>----------------------------------------------------------------
>(eval-when (compile eval)
>  (defmacro while (test &body body)
>    `(loop while ,test do ,@ body))
>  #+nil
>  (defmacro f (op x y)
>    `(,op (the fixnum ,x) (the fixnum ,y))))
>----------------------------------------------------------------
>
>When I use cl-info with GCL, I get:
>----------------------------------------------------------------
>(%i1) ? plot_options
>
>Maxima encountered a Lisp error:
>
> Error in WHEN [or a callee]: The function CL-INFO::WHILE is undefined.
>----------------------------------------------------------------
>
>CMUCL and Clisp work fine. I can fix the problem by changing the snippet
>to
>----------------------------------------------------------------
>#+gcl
>(defmacro while (test &body body)
>    `(loop while ,test do ,@ body))
>
>(eval-when (compile eval)
>  #-gcl
>  (defmacro while (test &body body)
>    `(loop while ,test do ,@ body))
>  #+nil
>  (defmacro f (op x y)
>    `(,op (the fixnum ,x) (the fixnum ,y))))
>----------------------------------------------------------------
>I don't understand why I should have to do this, however. Any insight
>would be appreciated.
>
>--Jim
>
>
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