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From: Gabriel Scherer <gabriel.scherer@gmail.com>
Date: Mon, 26 May 2014 17:33:31 +0200
Message-ID: <CAPFanBG2jLRMnHFoyvh7rfRYP98J3DzBBnauK2J2RGJVZB3uKw@mail.gmail.com>
To: Philippe Veber <philippe.veber@gmail.com>
Cc: caml users <caml-list@inria.fr>
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Subject: Re: [Caml-list] Uncaught exceptions in function type.

The problem is with functions taken as parameter. What would be the
exception signature of List.map?

This work has already been done by Fran=C3=A7ois Pessaux in the "ocamlexc"
project, using row variables to infer convenient exception typings.
The problem is that he basically had to re-implement a full
type-checker for OCaml to do this, which grew unmaintained (it was a
PhD work) and is probably unusable today. There is of course interest
in reviving it (looking for simpler or integrated-upstream approaches
to reduce the maintenance burden), and he recently made the ocamlexc
sources available online for this purpose. If anyone is tempted to
contribute...

On Mon, May 26, 2014 at 4:23 PM, Philippe Veber
<philippe.veber@gmail.com> wrote:
> Hi everyone,
>
> Out of curiosity, I was wondering how difficult it would be in theory to
> extend the type system so that exceptions that can pop out of a function
> when it is called would be included in the type of the function. Could th=
is
> type information be infered automatically? Could this be used to have an
> exhaustivity check in the "with" part of a try ... with expression?
>
> I guess that if it was so easy, we would already be enjoying it within our
> favorite compiler, but I fail to see how hairy is the question.
>
> Cheers,
>   Philippe.
>
>