Mailing list for all users of the OCaml language and system.
 help / color / mirror / Atom feed
From: "Vesa Karvonen" <vesa.karvonen@housemarque.fi>
To: <caml-list@inria.fr>
Subject: Re: [Caml-list] Bug in Hashtbl ?
Date: Thu, 21 Mar 2002 18:07:34 +0200	[thread overview]
Message-ID: <009b01c1d0f2$83743a60$422aa8c0@housemarque.fi> (raw)
In-Reply-To: <Pine.SOL.4.44.0203211642001.1625-100000@clipper.ens.fr>

Thanks to everyone for the quick replies.

From: "Alain Frisch" <frisch@clipper.ens.fr>
> On Thu, 21 Mar 2002, Vesa Karvonen wrote:
> >
> > The following program raises an Out_of_memory exception. Is this:
> > - correct behavior,
> > - bug in Ocaml 3.04, or
> > - bug somewhere else?
>
> I would say "correct behavior"; the manual says, about generic
> comparisons:
>
>      Comparison between cyclic structures may not terminate.

Yep, this seems to be the problem.

It might be wise to specifically mention in the Hashtbl documentation that the
functorial version is needed for cyclic structures. The Hashtbl.hash function
documentation easily gices the wrong impression.

> Note that it would be costly to implement exact (structural) comparison of
> cyclic structures (with a coinductive definition). What you want is
> probably to test for physical equality; you can use the functorial version
> of hash tables to do that.

The code is actually a stripped down version of a unit test, so it is not a
problem to change to an acyclic representation. The application isn't using
cyclic structures.

Regards,
  Vesa Karvonen


-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners


  reply	other threads:[~2002-03-21 16:02 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-03-21 15:35 Vesa Karvonen
2002-03-21 15:46 ` Alain Frisch
2002-03-21 16:07   ` Vesa Karvonen [this message]
  -- strict thread matches above, loose matches on Subject: below --
2002-03-21 15:27 Vesa Karvonen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='009b01c1d0f2$83743a60$422aa8c0@housemarque.fi' \
    --to=vesa.karvonen@housemarque.fi \
    --cc=caml-list@inria.fr \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox