On Sun, Jul 21, 2002 at 01:05:58PM +0200, Diego Gomez Deck wrote:
> >NOTE: Both forms shown here (original form, classic Smalltalk form) will
> >compile and produce the exact same code and behavior. With the noted
> >comments where I removed some extra annotations and replaced them with
> >comments.
> 
> In ST you can write code like that:
> 
> Point>>+ anObject
>      ^ anObject addToPoint: self.
> 
> Point>>addToPoint: aPoint
>      ^ (self x + aPoint x) @ (self y + aPoint y)
> 
> Number>>addToPoint: aPoint
>      ^ (self + aPoint x) @ (self + aPoint y)
> 
> String>>addToPoint: aPoint
>      ^ (self asNumber + aPoint x) @ (self asNumber + aPoint y)
> 
> My point is: The gain don't pay the complexity added to the language.

The double-dispatch pattern works fine if you are only dispatching on
two types.  However, if you are dispatching on 3 or more, it is much
nicer to have real multi-method dispatch.

Joshua