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To: caml-list@inria.fr
Subject: Re: Tree of a certain class: 
In-Reply-To: Your message of "Fri, 24 Sep 1999 10:15:52 +0200."
             <37EB3338.4E226250@unibw-muenchen.de> 
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Date: Fri, 24 Sep 1999 14:18:54 +0200
From: "Sylvain BOULM'E" <Sylvain.Boulme@lip6.fr>
Sender: weis

Hello,

Actually, #debug is an abbrevation for 
 <method debug : unit; ..>
where ".." is a row type variable, you may imagine as universally quantified.
And methods of a class are not allowed to be polymorphic. Only classes are.
So, you have to bound this row variable to a type parameter of the class. 

* So a general solution is :

class ['a] dtree =
  object
    constraint 'a=#debug
    inherit ['a] ctree
  end

* But if you want only a "debug tree", you may write :

class dtree =
  object
    inherit [debug] ctree
  end

Regards,

Sylvain.