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Message-ID: <3D8C2F45.7080604@baretta.com>
Date: Sat, 21 Sep 2002 10:35:17 +0200
From: Alessandro Baretta <alex@baretta.com>
Organization: Baretta srl -- www.baretta.com
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To: Ocaml <caml-list@inria.fr>
Subject: Re: [Caml-list] Polymorphic methods and ellipsis
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Pixel wrote:
> Alessandro Baretta <alex@baretta.com> writes:
> 
> 
>>I'm trying to write a polymorphic method that will accept as a parameter any
>>instance of any subclass of given class. For example
> 
> 
> what about the simpler:
> 
> class salutation = object
>    method greet : 'a. (#parent as 'a) -> string = fun obj -> obj # foo ^ obj # bar
> end
> 
> which works :)

True. I remember trying something of this kind last night, 
but I probably did not use the fun construct to define the 
obj parameter, so it did not work.

At any rate, why does my technique not work?

class salutation : object
   method greet : 'a. (#parent as 'a) -> string
end = object
   method greet obj -> obj # foo ^ obj # bar
end


Alex

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