From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <ober.14@osu.edu>
X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on yquem.inria.fr
X-Spam-Level: 
X-Spam-Status: No, score=0.4 required=5.0 tests=AWL,DNS_FROM_RFC_ABUSE 
	autolearn=disabled version=3.1.3
Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104])
	by yquem.inria.fr (Postfix) with ESMTP id 07BA2BC69
	for <caml-list@yquem.inria.fr>; Sat,  5 Jan 2008 20:41:03 +0100 (CET)
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: Aq4HAGVsf0dDWxLC/2dsb2JhbACBV6gR
X-IronPort-AV: E=Sophos;i="4.24,249,1196636400"; 
   d="scan'208";a="7468828"
Received: from ip67-91-18-194.z18-91-67.customer.algx.net (HELO server1.bertec.net) ([67.91.18.194])
  by mail3-smtp-sop.national.inria.fr with ESMTP; 05 Jan 2008 20:41:02 +0100
Received: from kuba.bertec.net (kuba.bertec.net [192.168.2.16])
	by server1.bertec.net (Postfix) with ESMTP id B0DB2105831
	for <caml-list@yquem.inria.fr>; Sat,  5 Jan 2008 14:41:01 -0500 (EST)
From: Kuba Ober <ober.14@osu.edu>
To: caml-list@yquem.inria.fr
Subject: Syntax ideas for non-uniform memory (near/far etc)
Date: Sat, 5 Jan 2008 14:41:00 -0500
User-Agent: KMail/1.9.6 (enterprise 0.20071123.740460)
MIME-Version: 1.0
Content-Type: text/plain;
  charset="us-ascii"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200801051441.00892.ober.14@osu.edu>
X-Spam: no; 0.00; syntax:01 non-uniform:01 ocaml:01 syntax:01 non-uniform:01 pointers:01 ocaml:01 compiler:01 cleanest:98 polymorphic:01 polymorphic:01 rec:01 syntactic:01 tuple:02 data:02 

I'm trying to adapt Ocaml syntax to embedded uses. There, memory is often
non-uniform and variables can live in different areas, say near/far/rom.

I was wondering what would be the "cleanest" syntax for that. I presume that
adding near/far/rom as keywords and using them similarly to "rec" would work,
e.g.

let print rom s = ... (* prints a string with a rom address *)

The truth is that "rom/near/far" is really part of the type, as if a function 
has a parameter living say in rom
then it won't take one in ram. So maybe one could have

let print (s : rom) = ....
of type string -> unit

For those unfamiliar with embedded work, think 16-bit x86 with near/far 
pointers and whatnot.

I'm all ears for other ideas as to how it might be implemented. Any syntactic 
sugar to make it cleaner looking?

I presume that an extension of this idea is to have multi-faceted types, where 
each type is really a tuple of "types", such that some could be polymorphic 
and some not.

Say one wants to have a function which will work on data put anywhere:

let print (s : 'c, string) = ....

where 'c is the "storage class", here polymorphic, and string is the good old 
type.

Of course none of this would use *the* OCaml compiler, I'm trying to write (or 
port, rather) my own.

Kuba