From: Jim Freeze <jim@...>
Date: 2003-04-28T08:51:19+09:00
Subject: Re: MathN

On Monday, 28 April 2003 at  7:16:39 +0900, Bret Jolly wrote:
> 
> # make infix operators in Numeric classes play nice with Pnom
> PlayNiceWithPnom = {'+'=>'Plus', '*'=>'Mul', '<=>'=>'Spaceship',
>   '=='=>'Equal', '<'=>'Less', '>'=>'Greater', '<='=>'LessEqual',
>   '>='=>'GreaterEqual'}
> PlayNiceWithPnom.each {|key, value|
>   eval(%Q% PlayNiceWithPnom#{value} = <<-EOS
> alias prePnom_#{value} #{key}
> def #{key}(other)
>   if defined?(Pnom) and other.kind_of?(Pnom)
>     Pnom.new(self) #{key} other
>   else
>     prePnom_#{value}(other)
>   end
> end
> EOS
> %)
> }
> ObjectSpace.each_object(Class) {|klass|
>   if klass.ancestors.include?(Numeric)
>     PlayNiceWithPnom.each{|key, value|
>       if klass.public_instance_methods.include?(key)
>         unless klass.public_instance_methods.include?("prePnom_#{value}")
>           eval(%Q%  klass.module_eval(PlayNiceWithPnom#{value})%)
>         end
>       end
>     }
>   end
> }       
> 
>    I shudder to think of trying to accomplish this in Python!

The above seems very interesting, but it is not clear to me
exactly how it works.

Would you mind providing a walk-thru description of what it does?

Thanks

-- 
Jim Freeze
----------
Don't change the reason, just change the excuses!
		-- Joe Cointment