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From: Jon Harrop <jonathandeanharrop@googlemail.com>
To: <orbitz@ezabel.com>
Cc: <caml-list@inria.fr>
References: <50AF76A1-30E0-4735-AFB2-88BB603899CE@ezabel.com> <77df810e993b3002f8b97622102da8dd.squirrel@mail.mpi-sws.org> <F325FC2E-D852-4A7A-8550-F77797392BD0@ezabel.com> <1297268092.24058.416.camel@thinkpad> <CA021A26-A96C-49C6-A1E0-80F03E8AB53E@univ-orleans.fr> <25000DA4-042A-437D-8082-10C70E1C740F@ezabel.com>
In-Reply-To: <25000DA4-042A-437D-8082-10C70E1C740F@ezabel.com>
Date: Wed, 9 Feb 2011 21:50:39 -0000
Organization: Flying Frog Consultancy
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Subject: RE: [Caml-list] Scoped Bound Resource Management just for C++?

Orbitz:
> Do they appear in C++?

Yes.

> I would a dtor takes care of that for you when it comes to streams.

Only when the dtor is called. If a thread is aborted or exit or abort are
called then the dtor may not be called and your resource may leak.

> How does one safely write code in Ocaml that guarantees resources will be
freed?  

You cannot so you make the best of a bad job and write code that catches
most errors in practice, like the code I gave. You might also add a
syntactic construct like F#'s "use" binding that makes this even simpler and
clearer but, ultimately, it is still not perfect.

Cheers,
Jon.