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Date: Sat, 29 Nov 2008 09:17:31 -0800 (PST)
From: Dario Teixeira <darioteixeira@yahoo.com>
Subject: Re: [Caml-list] Issues with Sexplib (#1)
To: Till Varoquaux <till.varoquaux@gmail.com>
Cc: caml-list@yquem.inria.fr
In-Reply-To: <9d3ec8300811290901l4d2596a9mef88e5f0f4bcb956@mail.gmail.com>
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X-Spam: no; 0.00; bug:01 camlp:01 sexp:01 cheers:01 wrote:01 caml-list:01 types:05 problem:05 i'd:06 extension:06 undesirable:07 phantom:07 practice:09 feature:09 wondering:09 

Hi,

> This is not really a bug; I'd qualify this as an "undesirable"
> feature: sexplib erases type information; for instance the
> representation of None* will always be the same and therefore
> will be desexpable to any other option type. You may also note
> that some other type have compatible representations. In
> practice it would be really hard for a camlp4 extension to keep
> track of types. In you case you could use custom converters and
> save the phantom type in the sexp.

Yes, I figured as much (see the last paragraph of my original
message).  I was just wondering if there was already a canned
solution to this sort of problem (or one in the works), before
I wrote a custom converter.

Cheers,
Dario Teixeira
=0A=0A=0A