From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <markus.mottl@gmail.com>
X-Original-To: caml-list@sympa.inria.fr
Delivered-To: caml-list@sympa.inria.fr
Received: from mail2-relais-roc.national.inria.fr (mail2-relais-roc.national.inria.fr [192.134.164.83])
	by sympa.inria.fr (Postfix) with ESMTPS id 9B59F7EE51
	for <caml-list@sympa.inria.fr>; Thu, 18 Apr 2013 22:11:12 +0200 (CEST)
Received-SPF: None (mail2-smtp-roc.national.inria.fr: no sender
  authenticity information available from domain of
  markus.mottl@gmail.com) identity=pra;
  client-ip=209.85.223.181;
  receiver=mail2-smtp-roc.national.inria.fr;
  envelope-from="markus.mottl@gmail.com";
  x-sender="markus.mottl@gmail.com";
  x-conformance=sidf_compatible
Received-SPF: Pass (mail2-smtp-roc.national.inria.fr: domain of
  markus.mottl@gmail.com designates 209.85.223.181 as permitted
  sender) identity=mailfrom; client-ip=209.85.223.181;
  receiver=mail2-smtp-roc.national.inria.fr;
  envelope-from="markus.mottl@gmail.com";
  x-sender="markus.mottl@gmail.com";
  x-conformance=sidf_compatible; x-record-type="v=spf1"
Received-SPF: None (mail2-smtp-roc.national.inria.fr: no sender
  authenticity information available from domain of
  postmaster@mail-ie0-f181.google.com) identity=helo;
  client-ip=209.85.223.181;
  receiver=mail2-smtp-roc.national.inria.fr;
  envelope-from="markus.mottl@gmail.com";
  x-sender="postmaster@mail-ie0-f181.google.com";
  x-conformance=sidf_compatible
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: AhYCAMBScFHRVd+1m2dsb2JhbABQDoMuwFt+CBYOAQEBAQEGCwsJFCiCHwEBBUABFAcdAQMMBgULAwouIQEBEQEFARwGEwiHeQEDD59PjC+Ce4R7ChknDVmIfgEFDIw5glMHg0cDlSSBY4t4gzoWKYNvWyA
X-IPAS-Result: AhYCAMBScFHRVd+1m2dsb2JhbABQDoMuwFt+CBYOAQEBAQEGCwsJFCiCHwEBBUABFAcdAQMMBgULAwouIQEBEQEFARwGEwiHeQEDD59PjC+Ce4R7ChknDVmIfgEFDIw5glMHg0cDlSSBY4t4gzoWKYNvWyA
X-IronPort-AV: E=Sophos;i="4.87,503,1363129200"; 
   d="scan'208";a="13926908"
Received: from mail-ie0-f181.google.com ([209.85.223.181])
  by mail2-smtp-roc.national.inria.fr with ESMTP/TLS/RC4-SHA; 18 Apr 2013 22:11:11 +0200
Received: by mail-ie0-f181.google.com with SMTP id tp5so1401705ieb.26
        for <caml-list@inria.fr>; Thu, 18 Apr 2013 13:11:10 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20120113;
        h=mime-version:x-received:in-reply-to:references:date:message-id
         :subject:from:to:cc:content-type;
        bh=50DESPwCwF3w5UMxfznOlcZao3obCgpAJKU62lv8HbY=;
        b=RjogOK7YBbBPfXKIFgitOXJNJQWfLJ2gDX8bTzW1oEIWRH8UKOLkYzwUgSYrF8TDsz
         sIqJSe1KJyi9JI/uwDGcD9qKKnH4lgkVcIWvZBL5scUSZSldDlWfX/lLwGunYlHv1qU5
         U7OigG/YBhCzIJYKPj/IY6Sf1om+ekrR2CYgeQQccDrjk7ARYT6L6xg5px0Eg+hvc6TX
         v5PS5rZ3tAEStX7Y4D7e87aa07v0RwByXFUGz85ZQ6RFJmG/dpXbghLlLvkeYgQcH61L
         zcXSm9ZM662zu6HtdGVbHgOsxlBmS33oC6lpQ0j2b0yonQSjPz6LQaFvFDvoE/A55dvZ
         QB1A==
MIME-Version: 1.0
X-Received: by 10.50.138.166 with SMTP id qr6mr13683136igb.45.1366315870687;
 Thu, 18 Apr 2013 13:11:10 -0700 (PDT)
Received: by 10.64.32.34 with HTTP; Thu, 18 Apr 2013 13:11:10 -0700 (PDT)
In-Reply-To: <201304181712.r3IHCbSC023593@outgoing.mit.edu>
References: <201304181712.r3IHCbSC023593@outgoing.mit.edu>
Date: Thu, 18 Apr 2013 16:11:10 -0400
Message-ID: <CAP_800rb=iwE5OyYfEXnG7dXih93wEPOJxM2RWxzKOfORkLi2A@mail.gmail.com>
From: Markus Mottl <markus.mottl@gmail.com>
To: John Carr <jfc@mit.edu>
Cc: caml-list@inria.fr
Content-Type: text/plain; charset=ISO-8859-1
Subject: Re: [Caml-list] Unpacked module parameterized type escaping

On Thu, Apr 18, 2013 at 1:12 PM, John Carr <jfc@mit.edu> wrote:
>
> I have a function of two arguments:
>
> 1. A packed module implementing Map.S.
>
> 2. A value of the module's Map.S.t.
>
> I can't find a way to prevent a "type constructor ... would escape its
> scope" error.

I think you may just want to wrap both the map module to be used and
the value on which its functions should operate in another first-class
module, e.g.:

  module type Arg = sig
    module M : Map.S with type key = int
    val v : 'a M.t
  end

Then you can write:

  let is_empty (module Arg : Arg) = Arg.M.is_empty Arg.v

This admittedly doesn't look particularly elegant, but should solve the problem.

Regards,
Markus

--
Markus Mottl        http://www.ocaml.info        markus.mottl@gmail.com