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From: David Rajchenbach-Teller <David.Teller@ens-lyon.org>
To: Fabrice Le Fessant <fabrice@lefessant.net>
Cc: Yitzhak Mandelbaum <yitzhakm@cs.princeton.edu>,
	OCaml mailing list <caml-list@inria.fr>
Subject: Re: [Caml-list] optional functions in modules
Date: Thu, 10 May 2012 16:59:54 +0200	[thread overview]
Message-ID: <4FABD7EA.7080902@ens-lyon.org> (raw)
In-Reply-To: <CAHvkLrNC5256HXxxvX8yNjSzy0cXST5xr-M_km6JrXhNhF+_+g@mail.gmail.com>

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I would personally use an [option] and a form of startup-time
configuration, quite comparable to the browser-feature detection in
JavaScript.

So, something like

let my_function = match Module.may_have_feature with
  | Some implementation -> implementation
  | None -> (*either a workaround or an error*)

Cheers,
 David

On 5/10/12 4:53 PM, Fabrice Le Fessant wrote:
> I would say that it depends on how likely it is that somebody is going
> to handle the case where the function is not implemented. I would use
> a boolean to detect if the function is implemented, and calling the
> missing function would raise an exception (be careful to define the
> corresponding exception, using failwith "not implemented" might be too
> generic to be useful, although I always do it in my programs ;-) ). If
> it is highly likely that the program is going to handle the missing
> function, using a Some type for the function is better idea.
> 
> -Fabrice
> 


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  reply	other threads:[~2012-05-10 15:00 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-10 12:22 Yitzhak Mandelbaum
2012-05-10 14:13 ` "Markus W. Weißmann"
2012-05-10 14:53 ` Fabrice Le Fessant
2012-05-10 14:59   ` David Rajchenbach-Teller [this message]
2012-05-10 18:44 ` Goswin von Brederlow
2012-05-11  0:55   ` Yaron Minsky
2012-05-17 17:43     ` Yitzhak Mandelbaum
2012-05-18 15:24       ` David Rajchenbach-Teller
2012-05-18 16:00         ` Gabriel Scherer
2012-05-18 20:05           ` Nicolas Braud-Santoni

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