From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on yquem.inria.fr X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=AWL autolearn=disabled version=3.1.3 X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from concorde.inria.fr (concorde.inria.fr [192.93.2.39]) by yquem.inria.fr (Postfix) with ESMTP id E0E1CBC69 for ; Sat, 10 Feb 2007 01:08:48 +0100 (CET) Received: from ptb-relay02.plus.net (ptb-relay02.plus.net [212.159.14.213]) by concorde.inria.fr (8.13.6/8.13.6) with ESMTP id l1A08mTw024921 (version=TLSv1/SSLv3 cipher=AES256-SHA bits=256 verify=NO) for ; Sat, 10 Feb 2007 01:08:48 +0100 Received: from [80.229.56.224] (helo=[10.0.0.5]) by ptb-relay02.plus.net with esmtp (Exim) id 1HFfnM-0001n1-1o for caml-list@yquem.inria.fr; Sat, 10 Feb 2007 00:08:48 +0000 From: Jon Harrop Organization: Flying Frog Consultancy Ltd. To: caml-list@yquem.inria.fr Subject: Re: [Caml-list] Amb Date: Sat, 10 Feb 2007 00:01:54 +0000 User-Agent: KMail/1.9.5 References: <1197BD5D-1373-4876-8DC1-FED84797E4A6@valdosta.edu> <45CCEDCC.1090200@janestcapital.com> In-Reply-To: <45CCEDCC.1090200@janestcapital.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200702100001.55094.jon@ffconsultancy.com> X-Miltered: at concorde with ID 45CD0D10.000 by Joe's j-chkmail (http://j-chkmail . ensmp . fr)! X-Spam: no; 0.00; recursion:01 recursive:01 recursive:01 ocaml:01 ocaml:01 amb:98 amb:98 frog:98 wrote:01 rec:01 caml-list:01 tail:01 match:02 slightly:03 ops:03 On Friday 09 February 2007 21:55, Brian Hurt wrote: > let rec amb = function > > | [] -> None > | h :: t -> > > let r = > try > Some(h ()) > with > > | _ -> None > > in > match r with > > | None -> amb t > | Some(_) as e -> e > > As a slightly better implementation. I think you're trying to box the returned value in order to evade non-tail recursion but the OPs function was actually already tail recursive because the recursive call to "amb" occurs outside the try..with. -- Dr Jon D Harrop, Flying Frog Consultancy Ltd. OCaml for Scientists http://www.ffconsultancy.com/products/ocaml_for_scientists