From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail1-relais-roc.national.inria.fr (mail1-relais-roc.national.inria.fr [192.134.164.82]) by walapai.inria.fr (8.13.6/8.13.6) with ESMTP id q46AxiVg025663 for ; Sun, 6 May 2012 12:59:44 +0200 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AkoBAEpZpk/RVda2imdsb2JhbAApGrJjCCIBAQEKCQ0HEgYjggwBAQEEEgIsARsdAQMMBgULDS4hAQERAQUBHAYTIoddAQMLCyqbTgkDjCSCc4QYChknDRVCiHYBBQuKDGiGIASVfoERiEmBZYMjPYQO X-IronPort-AV: E=Sophos;i="4.75,538,1330902000"; d="scan'208";a="156937581" Received: from mail-ob0-f182.google.com ([209.85.214.182]) by mail1-smtp-roc.national.inria.fr with ESMTP/TLS/RC4-SHA; 06 May 2012 12:59:38 +0200 Received: by obcni5 with SMTP id ni5so11445340obc.27 for ; Sun, 06 May 2012 03:59:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; bh=PgmdovVshQhj7tz4t25jfgWRTLDb7ctN2ekETcR1RNA=; b=Hxd/J9qBFPvXWduyVYTqKnqmd3GfzbcXXi9iantBELi2YtF0CKTT31dKwpo2/Q2XMq /GnHtHLP7lwgluXa0BSqMyYgp/y77azezsB0NZdOyWUSmQrlt4B/mvIZAvzmzQ2j6FRt 5aWJsMmi7Pv9ZtiqsCjUHfSrC1TXVx+I2ew6C1dv3FIToaAzuEw5mQBEF7L3qAgFgg0m fHnWrtvME6VVGICQ7uZFo2jqD/Amcpo/DcKE15AT+s2ERxtkGhYPd4u4xLgj98s6r3hk Tba86K411kYNhzSPQEHSLrkCG+Zd4dwsgRT6C64+JmW7WG94Kiwvl32UlHCbyQdAQjvt z1lQ== Received: by 10.50.185.161 with SMTP id fd1mr6199555igc.70.1336301977437; Sun, 06 May 2012 03:59:37 -0700 (PDT) MIME-Version: 1.0 Received: by 10.50.140.100 with HTTP; Sun, 6 May 2012 03:58:57 -0700 (PDT) In-Reply-To: <87fwbdsidx.fsf@frosties.localnet> References: <87lil64p0p.fsf@frosties.localnet> <87fwbdsidx.fsf@frosties.localnet> From: Gabriel Scherer Date: Sun, 6 May 2012 12:58:57 +0200 Message-ID: To: Goswin von Brederlow Cc: caml-list@inria.fr Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by walapai.inria.fr id q46AxiVg025663 Subject: Re: [Caml-list] How do I declare a value of 'a t instead of '_a t in a module? I agree this could be a good item in the FAQ. I have created an issue on the bugtracker for this. http://caml.inria.fr/mantis/view.php?id=5607 Do not hesitate to comment on the bug: suggestions of wording are warmly welcome. On Sun, May 6, 2012 at 12:39 PM, Goswin von Brederlow wrote: > Gabriel Scherer writes: > >> You need to specify in the signature that ('a t) is contravariant: >>   type +'a t > > Thanks, that was what I was looking for. Why can I never find this in > the docs when I need it? :) > > MfG >        Goswin