From: oinkoink+unet@... (Bret Jolly)
Date: 2003-05-04T15:34:13+09:00
Subject: Re: MathN

oinkoink+unet@rexx.com (Bret Jolly) wrote in message news:<7e7131a1.0305031356.174fec7e@posting.google.com>...
>   If these conditions hold, I use klass.module_eval
> to insert the definition in the class klass.

   That was pretty slick, wasn't it?  Such slickness
can produce inscrutable bugs.  The last bit of code,
which I meant to repeat but lost somehow, was this:

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 was just patting myself on the back for being
so clever when I ran into a bug.  This wasn't working
properly for Bignum '>'.  I investigated Bignum:

irb(main):001:0> Bignum.public_instance_methods
=> ["**", "quo", "<=>", "-", "coerce", "==", "[]", "modulo", "|",
 "/", "size", "eql?", "<<", "%", ">>", "~", "&", "divmod", "to_s",
 "hash", "^", "abs", "to_f", "div", "*", "remainder", "+", "-@"]
irb(main):002:0> Bignum.ancestors
=> [Bignum, Integer, Precision, Numeric, Comparable, Object, Kernel]

   Bignum gets its comparison methods >, <, >=, <= from
Comparable via the spaceship <=>, so they weren't listed
in Bignum.public_instance_methods, and my clever hack failed.
I kluged my way around it, and now I'm trying to think of
something better than a kluge.

                             Regards, Bret