GNU bug report logs - #21900
map is not continuation-safe

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Zefram <zefram <at> fysh.org>
To: bug-guile <at> gnu.org
Subject: map is not continuation-safe
Date: Fri, 13 Nov 2015 08:34:21 +0000

With Guile 2.0.11:

scheme@(guile-user)> (define cc #f)
scheme@(guile-user)> (map (lambda (v) (if (= v 0) (call/cc (lambda (c) (set! cc c) 0)) (+ v 1))) '(10 20 30 0 40 50 60))
$1 = (11 21 31 0 41 51 61)
scheme@(guile-user)> (cc 5)
$2 = (61 51 41 0 31 5 41 51 61)

It worked correctly in Guile 1.8.

-zefram

Message #10 received at 21900-done <at> debbugs.gnu.org (full text, mbox):

From: Andy Wingo <wingo <at> pobox.com>
To: Zefram <zefram <at> fysh.org>
Cc: 21900-done <at> debbugs.gnu.org
Subject: Re: bug#21900: map is not continuation-safe
Date: Mon, 20 Jun 2016 18:01:35 +0200

On Fri 13 Nov 2015 09:34, Zefram <zefram <at> fysh.org> writes:

> With Guile 2.0.11:
>
> scheme@(guile-user)> (define cc #f)
> scheme@(guile-user)> (map (lambda (v) (if (= v 0) (call/cc (lambda (c) (set! cc c) 0)) (+ v 1))) '(10 20 30 0 40 50 60))
> $1 = (11 21 31 0 41 51 61)
> scheme@(guile-user)> (cc 5)
> $2 = (61 51 41 0 31 5 41 51 61)
>
> It worked correctly in Guile 1.8.

"Fixed" in the upcoming 2.2 release, though I think we consider this
more of an implementation detail than a bug.

Andy

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