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From: jeff@aiva.ed.ac.uk (Jeff Dalton)
Newsgroups: comp.lang.lisp
Subject: Re: Question about eval
Message-ID: <621@aiva.ed.ac.uk>
Date: 15 Oct 88 17:15:21 GMT
References: <13733@iuvax.cs.indiana.edu>
Reply-To: jeff@uk.ac.ed.aiva (Jeff Dalton)
Organization: Dept. of AI, Univ. of Edinburgh, UK
Lines: 26

In article <13733@iuvax.cs.indiana.edu> dfried@iuvax.cs.indiana.edu (Dan Friedman) writes:
>Are there any LISP implementations, especially of Common LISP,
>which get 5 instead of 1 as the result of the following run?
> (defun eval (x) 1); then 5 => 1

Yes, KCL.

>Does this change to eval ever change what load does?

No.

>Does (setf (symbol-function 'eval) #'(lambda (x) 1))
>do exactly the same thing as (defun eval (x) 1) in all 
>Common Lisp implementations?

Probably not.  DEFUN puts in a BLOCK, for one thing.  Also,
I dont' think there's anyhting that requires it to set the
function value exactly the same way SETF of SYMBOL-FUNCTION
does.

If you want to redefine EVAL and be sure it works, I think
you have to make a new package that shadows EVAL and LOAD,
redefines them, and (depending on how you want to do this)
exports all the other symbols the LISP package does.

-- Jeff