Re: [Caml-list] does class polymorphism need to be so complicated?

[Richard Jones <rich@annexia.org>]

On Wed, Aug 20, 2003 at 11:05:35AM -0500, Brian Hurt wrote:
> Instead of declaring obj to be printable, why not just declare that it has 
> a function print?  Like:
> 
> class printer = 
>     object
>         method print (obj: <print: unit->unit>) = obj#print ();
>     end;;
> 
> This removes the need for a coercion, as it gets around the need to 
> upcast.

Interesting. Am I right in thinking that the <print : unit -> unit>
type syntax can refer to _any_ object which has a print method,
regardless of class hierarchy?

This could be quite a fun feature, although I'm not quite sure of the
best way to use it ...

Rich.

-- 
Richard Jones. http://www.annexia.org/ http://freshmeat.net/users/rwmj
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