From: Vicente Bosch Campos <vbosch@...>
Date: 2011-03-26T00:19:55+09:00
Subject: Re: Dynamically calling a certain set of methods

If I add the method with instance_eval you are correct, but it works if we add them to the class definition with class_eval (hence they get inherited).

#! /usr/bin/env ruby

require 'ap'

class Foo
  def new_create
    instance_eval do 
      def xMutation 
        puts "XELLO"
      end
    end
    Foo.class_eval do 
      def yMutation 
        puts "YELLO"
      end
    end      
  end
end

class Bar < Foo
end

a = Foo.new
a.new_create
ap a.methods.grep(/Mutation\z/)
b = Bar.new
ap b.methods.grep(/Mutation\z/)
a.xMutation
a.yMutation
b.yMutation
#b.xMutation  <- Fails
ap Foo.methods.grep(/Mutation\z/) #We have not added any class methods, which is what we wanted

In any case I want to do something more dynamic than this and not force the new definitions to the class definition. I am sort of like having a "Library of Congress" singleton class where the new methods created on the fly and the scores obtained with them are stored. Hence when the new objects get created they go into the library and apply to themselves the methods that worked well for past generations ( with a random factor because we want innovation). Its a bit like genetics but with historical memory ? 

Kind regards,
Vicente

On Mar 25, 2011, at 10:13 AM, Albert Schlef wrote:

> Simon Kaczor wrote in post #989060:
>> class Mutating
>>  ...
>>  @mutations = instance_methods.grep(/Mutation$/)
>>  class << self
>>    attr_reader :mutations
>>  end
> 
> But if his actual class if derived from Mutating, your code won't work 
> because the derived class won't see the parent's @mutations. Correct me 
> if I'm wrong.
> 
> -- 
> Posted via http://www.ruby-forum.com/.
>