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From: Gabriel Scherer <gabriel.scherer@gmail.com>
Date: Fri, 18 Jan 2013 19:27:14 +0100
Message-ID: <CAPFanBGqAdTe2uujQGtxYVrj-W5Y_Ez0Xu0_fgrY2OttekYzgw@mail.gmail.com>
To: Jean-Baptiste Jeannin <jeannin@cs.cornell.edu>
Cc: Nicholas Lucaroni <nicholas.r.lucaroni@gmail.com>, Edgar Friendly <thelema314@gmail.com>, 
	"caml-list@inria.fr" <caml-list@inria.fr>
Content-Type: text/plain; charset=ISO-8859-1
Subject: Re: [Caml-list] Hash function: complexity and circular structures

A blunt point of view: comparing implicitly circular structures is a
sure road to hell, and you should use an explicit representation of
circularity (eg. with a element that just means "nothing here, you
should rewind to the other side") that will not blow up at each
occasion it gets -- and is generally much more flexible.

On Fri, Jan 18, 2013 at 6:46 PM, Jean-Baptiste Jeannin
<jeannin@cs.cornell.edu> wrote:
>
> I would be curious to know if this is by design (it is supposed not to
> work), or if it is a problem with the implementation of compare, or of
> Hashtbl.find. In particular, if it is by design, why have updated the hash
> function to support circular lists?
> I am also now stuck on creating an (efficient) hashtable supporting circular
> data structures as keys. Any idea on this?