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From: Goswin von Brederlow <goswin-v-b@web.de>
To: Jacques-Henri Jourdan <jacques-henri.jourdan@normalesup.org>
Cc: caml-list@inria.fr
Subject: Re: [Caml-list] ocaml 4.03 and warning 52 : argument of this constructor should not be matched against a constant pattern
Date: Thu, 28 Apr 2016 09:25:58 +0200	[thread overview]
Message-ID: <20160428072558.GA10554@frosties> (raw)
In-Reply-To: <57208EA3.6030801@normalesup.org>

On Wed, Apr 27, 2016 at 12:04:19PM +0200, Jacques-Henri Jourdan wrote:
> I think it has been introduced in 4.02.
> 
> On 04/27/2016 12:00 PM, Daniel Bünzli wrote:
> > Le mercredi, 27 avril 2016 à 11:43, Jacques-Henri Jourdan a écrit :
> >> Or, with the new pattern matching with exception syntax :
> >>  
> >> match List.hd lst with
> >> | exception Failure _ -> Printf.printf "empty list\n"
> >> | hd -> ...
> > When was that introduced again ? I'm now starting to move to 4.01 language-wise.  
> >
> > Daniel

That's rarther stupid in this case. Why create and catch an exception
when you can just match the list directly?

    match lst with
    | [] -> Printf.printf "empty list\n"
    | hd::_ -> ...

MfG
	Goswin

  reply	other threads:[~2016-04-28  7:26 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-27  9:22 William
2016-04-27  9:28 ` David Allsopp
2016-04-27  9:36 ` Daniel Bünzli
2016-04-27  9:43   ` Jacques-Henri Jourdan
2016-04-27  9:51     ` Roberto Di Cosmo
2016-04-27 10:00     ` Daniel Bünzli
2016-04-27 10:04       ` Jacques-Henri Jourdan
2016-04-28  7:25         ` Goswin von Brederlow [this message]
2016-04-27 11:01 ` Gabriel Scherer
2016-04-27 17:17   ` Adrien Nader
2016-04-27 18:20     ` Gabriel Scherer

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