From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <bobzhang1988@gmail.com>
X-Original-To: caml-list@sympa.inria.fr
Delivered-To: caml-list@sympa.inria.fr
Received: from mail4-relais-sop.national.inria.fr (mail4-relais-sop.national.inria.fr [192.134.164.105])
	by sympa.inria.fr (Postfix) with ESMTPS id C3AD97ED34
	for <caml-list@sympa.inria.fr>; Wed, 11 Jul 2012 04:42:40 +0200 (CEST)
Received-SPF: None (mail4-smtp-sop.national.inria.fr: no sender
  authenticity information available from domain of
  bobzhang1988@gmail.com) identity=pra;
  client-ip=209.85.216.47;
  receiver=mail4-smtp-sop.national.inria.fr;
  envelope-from="bobzhang1988@gmail.com";
  x-sender="bobzhang1988@gmail.com";
  x-conformance=sidf_compatible
Received-SPF: Pass (mail4-smtp-sop.national.inria.fr: domain of
  bobzhang1988@gmail.com designates 209.85.216.47 as permitted
  sender) identity=mailfrom; client-ip=209.85.216.47;
  receiver=mail4-smtp-sop.national.inria.fr;
  envelope-from="bobzhang1988@gmail.com";
  x-sender="bobzhang1988@gmail.com";
  x-conformance=sidf_compatible; x-record-type="v=spf1"
Received-SPF: None (mail4-smtp-sop.national.inria.fr: no sender
  authenticity information available from domain of
  postmaster@mail-qa0-f47.google.com) identity=helo;
  client-ip=209.85.216.47;
  receiver=mail4-smtp-sop.national.inria.fr;
  envelope-from="bobzhang1988@gmail.com";
  x-sender="postmaster@mail-qa0-f47.google.com";
  x-conformance=sidf_compatible
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: AiMCAFTn/E/RVdgvk2dsb2JhbABFDrdpCCIBAQEBCQkLCRQEI4IgAQEBBAEBAQ8CJAgBGxILAQMMBgULDQklDwISEQEFARwGDQEHAQEeh1sBAwyeVgkDjCOCcYUQChknDVeIcQEFDJEiA5U2jig+g0VV
X-IronPort-AV: E=Sophos;i="4.77,564,1336341600"; 
   d="scan'208";a="150260002"
Received: from mail-qa0-f47.google.com ([209.85.216.47])
  by mail4-smtp-sop.national.inria.fr with ESMTP/TLS/RC4-SHA; 11 Jul 2012 04:42:39 +0200
Received: by qabg1 with SMTP id g1so2989568qab.6
        for <caml-list@inria.fr>; Tue, 10 Jul 2012 19:42:38 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20120113;
        h=message-id:date:from:user-agent:mime-version:newsgroups:to:cc
         :subject:references:in-reply-to:content-type
         :content-transfer-encoding;
        bh=OD9wxEDGFifxtVDgtEclygbcu/Cs+1KgPfJhn/5VGMs=;
        b=UJIP79L3wNpD9aNvOuQjkipI346YMyx/4cfvEus8wC8X4tlbz8+1XJl9O7GrVF42Ed
         Cp/p6qWKnLw/nSV36Dd4zRE4UkV2A8OViIOLdRJJV+v/Z2y09U9FmR1pP9s8rsSvlG9e
         37z6xkXs/PtZLWPQJypHXbOv4Dc8WRtzzeTWyixQPZ5t8FsbUtC8McKeQj3NJlENR7mv
         ctwXxOoVdi76kc1HHJUYTketbkXdbCdfE0KfevYtzryELzNa9fY+NL8kDzkV9ou+3wI1
         1/TcnA72V7Rl0vV9ac+8uum5YxTwzf7hepmAXo7uRHZzv45tY9Uy9Po0oH3hY6oacZk+
         PHYg==
Received: by 10.224.72.210 with SMTP id n18mr83960923qaj.10.1341974558527;
        Tue, 10 Jul 2012 19:42:38 -0700 (PDT)
Received: from Hongbos-MacBook-Air.local ([66.250.143.158])
        by mx.google.com with ESMTPS id fx5sm1525222qab.14.2012.07.10.19.42.37
        (version=SSLv3 cipher=OTHER);
        Tue, 10 Jul 2012 19:42:37 -0700 (PDT)
Message-ID: <4FFCE81A.80700@gmail.com>
Date: Tue, 10 Jul 2012 22:42:34 -0400
From: Hongbo Zhang <bobzhang1988@gmail.com>
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0) Gecko/20120614 Thunderbird/13.0.1
MIME-Version: 1.0
Newsgroups: gmane.comp.lang.caml.inria
To: Jean-Baptiste Jeannin <jeannin@cs.cornell.edu>
CC: "caml-list@inria.fr" <caml-list@inria.fr>
References: <A7FC6DE86AF33142A1FA4CE04EEBF4F18591C61822@gobo.cs.cornell.edu>
In-Reply-To: <A7FC6DE86AF33142A1FA4CE04EEBF4F18591C61822@gobo.cs.cornell.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Subject: [Caml-list] Re: Returning an element computed with Toploop

On 7/10/12 11:08 AM, Jean-Baptiste Jeannin wrote:
> Hello all,
>
Hi,
> Thanks to Jonathan Kimmitt on this mailing list, I learned about the existence of the Toploop module, that allows to execute OCaml code from a string. For example, one can do:
>
> # Toploop.execute_phrase true Format.err_formatter
> ((!Toploop.parse_toplevel_phrase) (Lexing.from_string "355./.113.;;"));;
> - : float = 3.14159292035398252
> - : bool = true
>
Use Tooploop.getvalue.
> However I could not find any official documentation of the module on the internet. In particular, the example above only prints out what was computed and returns a boolean (true or false), depending on how the computation terminated. I would like to compute an element and get the element back to be able to use it later in the computation. Is that possible and how could I do it?
>
The codebase for toplevel/ is pretty small, IMHO, reading the source is 
best way to understand how toploop works.

There's another non-trivial example in camlp4/Camlp4Top which shows you 
how to customize toplevel. If you understand how it works, feel free to 
use it, it's pretty safe :-)
> Thanks a lot,
> Jean-Baptiste
>