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From: Hugo Ferreira <hmf@inescporto.pt>
To: caml-list@yquem.inria.fr
Subject: Defining type that requires hashtables with recursive definition
Date: Mon, 19 Jan 2009 17:26:02 +0000	[thread overview]
Message-ID: <4974B7AA.9010004@inescporto.pt> (raw)

Hello,

I am attempting to define a type so:

type node =
   | Node of links
   | Leaf of int

And I want to implement links as a
hashtable whose keys and values are
also of type node. Note that the idea
is to use object address comparison
for the keys so:

module H =
   struct
     type t = node
     let equal (e1:node) (e2:node) = (==) e1 e2
     let hash (e:node) = Hashtbl.hash e
   end

module J = Hashtbl.Make( H )

However this requires a recursive definition on
the hashtable. How may a declare node and hashtable
to allow this?

TIA,
Hugo F.




             reply	other threads:[~2009-01-19 17:26 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-19 17:26 Hugo Ferreira [this message]
2009-01-19 17:34 ` [Caml-list] " Jacques Carette
2009-01-19 18:03   ` Thomas Gazagnaire
2009-01-19 19:36     ` Hugo Ferreira
2009-01-20 10:09     ` Hugo Ferreira
2009-01-19 19:34   ` Hugo Ferreira

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