Mailing list for all users of the OCaml language and system.
 help / color / mirror / Atom feed
From: "Loup Vaillant" <loup.vaillant@gmail.com>
To: "Oliver Bandel" <oliver@first.in-berlin.de>
Cc: caml-list@yquem.inria.fr
Subject: Re: [Caml-list] Concatenation of static strings?
Date: Fri, 25 Jan 2008 11:47:37 +0100	[thread overview]
Message-ID: <6f9f8f4a0801250247w37d4c66q1b268e47a72ecabf@mail.gmail.com> (raw)
In-Reply-To: <1201226223.479941ef07943@webmail.in-berlin.de>

2008/1/25, Oliver Bandel <oliver@first.in-berlin.de>:
> Zitat von Ashish Agarwal <agarwal1975@gmail.com>:
>
> > I was hoping there would be some follow up discussion on the code
> > below, but
> > haven't seen anything yet.
> [...]
>
> [...]
> It behaves like if s would be defined on top of the
> module, but it is  local constructed in the function f.
> Look sstrange... I have the same behaviour here (Debians
> OCaml here is 3.09.2, and I have tried with toplevel, bytecode
> and naticecode).

Ouch: this is the same as in C: the attempt to modify a statically
defined string makes bad things happen. One should try this on Open
BSD: it may even crash, if the the data segment is protected from
write. Replacing "abc" by String.copy "abc" works around this, though:

# let f () = let s = String.copy "bla" in let c = s.[0] in s.[0] <- 'c' ; c ;;
val f : unit -> char = <fun>
# f();;
- : char = 'b'
# f();;
- : char = 'b'

Pure again :-)

Cheers,
Loup


  reply	other threads:[~2008-01-25 10:47 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-19  3:32 Erik de Castro Lopo
2008-01-19  6:50 ` [Caml-list] " David Allsopp
2008-01-19  7:36   ` Erik de Castro Lopo
2008-01-19 10:55 ` David Baelde
2008-01-24 23:02   ` Ashish Agarwal
2008-01-25  1:57     ` Oliver Bandel
2008-01-25 10:47       ` Loup Vaillant [this message]
2008-01-26 13:27         ` Ashish Agarwal
2008-01-26 16:13     ` Jon Harrop
2008-01-26 19:58       ` Oliver Bandel

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=6f9f8f4a0801250247w37d4c66q1b268e47a72ecabf@mail.gmail.com \
    --to=loup.vaillant@gmail.com \
    --cc=caml-list@yquem.inria.fr \
    --cc=oliver@first.in-berlin.de \
    /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