Re: gensym with multiple-value-bind

On 17 Oct 2005 02:50:43 -0700, "Kaz Kylheku" <kkylheku@xxxxxxxxx> wrote:

> For instance in a LOOP, you can (RETURN) which breaks out the loop.
> That shadows any lexical function or macrolet named RETURN. Or, more
> precisely CL:RETURN.

I think you're not right here. First, from my understanding of
11.1.2.1.2 you can't lexically bind CL:RETURN as a function or macro
anyway in conforming programs. There are some implementations which
won't complain but in that case the lexical function isn't shadowed by
LOOP. LispWorks:

CL-USER 1 > (flet ((return (x) (print (list 'foo x))))
(loop for i below 10 when (oddp i) do (return i)))

(FOO 1)
(FOO 3)
(FOO 5)
(FOO 7)
(FOO 9)
NIL

Second, there's the LOOP /keyword/ RETURN but LOOP keywords are
recognized by name (STRING=) not by symbol identity:

CL-USER 1 > (defpackage my-package)
#<PACKAGE MY-PACKAGE>

CL-USER 2 > (loop for i below 10 when (oddp i) my-package::return i)
1

Cheers,
Edi.

--

Lisp is not dead, it just smells funny.

Real email: (replace (subseq "spamtrap@xxxxxxxxxx" 5) "edi")
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