On Friday, February 7, 2003, at 08:05 AM, dblack / candle.superlink.net 
wrote:

>   class SpecializedString < String
>     def to_i(s)
>       # specialized overriding of to_i
>     end
>   end
>
>   s = SpecializedString.new("12345")
>   m = /(\d\d)/.match(s)
>   n = m[1].to_i
>   p n * 10
>
>

This regexp change is actually very cool.  I've got some ugly code that 
I can fix
up as a result of this change.

FWIW I think your example argues more strongly for adding 
multi-dispatch to ruby (or
maybe just adopting a policy of not changing the semantics of 
well-known methods
in subclasses) than for backing out this change.