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Date: -- (:)
From: Narayanan Krishnamurthy <Narayanan.Krishnamurthy@m...>
Subject: [Caml-list] Re: Polymorphic methods in class objects
Ooops!! I'd a typo  and I've
changed it below.
Thanx.

Narayanan Krishnamurthy wrote:
> 
> Hi,
> 
> This is probably a very naive question,
> but I'm going to ask it anyways.
> I was trying to define a polymorphic
> method 'foo' as shown in the class below,
> but have not been able to compile it in Ocaml
> because of type unification problems.
> I'm not sure why this is not possible,
> since the compiler should be able to build a variant type
> automatically as the value of the expression 'foo'.
> Is there a fundamental reason or is it because
> it is against the principle of strong typing.
> 
> Other than defining variant types to deal
> with this, is there any other solution?
> Any help would be greatly appreciated.
> Thanx.
> 
> (*********************************************)
> class polym =
>   object(self)
>     val i = 0
>     method private func1 j = j + 1
>     method private func2 j = string_of_int j
>     method private func3 j = float_of_int j
>     method private foo polymf n =
>       polymf n
>     method goo () =
>       self#foo self#func1 2
>     method hoo () =
>       self#foo self#func2 2
>     method boo () =
>       self#foo self#func3 2
>   end
> 
> (* I would like to do the following *)
> let m = new polym
> 
> m#goo ()  returns 3
> m#hoo ()  returns "2"
> m#boo ()  returns "2.0"
> 
> (****************************************************)
> --
> **************************************************************************
> Narayanan Krishnamurthy (Nari)
> ASP Advanced Tools and Methodology
> Motorola SPS Architecture and Systems Platforms
> Motorola Inc. Semiconductor Products Sector
> 7700 W. Parmer Lane, Austin, TX 78729
> 
> Loc/MD: TX32/PL30         _
> email : nari@ibmoto.com /   \ email:
> Narayanan.Krishnamurthy@motorola.com
> Ph    : (512) 996-4863  |O O| Fax : (512) 996-7432
> ************************| I
> |*********************************************
>                         \ o /
>                          ---

-- 
**************************************************************************
Narayanan Krishnamurthy (Nari)
ASP Advanced Tools and Methodology
Motorola SPS Architecture and Systems Platforms
Motorola Inc. Semiconductor Products Sector
7700 W. Parmer Lane, Austin, TX 78729

Loc/MD: TX32/PL30         _
email : nari@ibmoto.com /   \ email:
Narayanan.Krishnamurthy@motorola.com 
Ph    : (512) 996-4863  |O O| Fax : (512) 996-7432 
************************| I
|*********************************************
		        \ o / 
                         ---
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