From: ts <decoux@...>
Date: 2006-05-14T21:05:01+09:00
Subject: Re: Making sense of the various Ruby "eval"s

>>>>> "P" == Pat Maddox <pergesu@gmail.com> writes:

P> define_method: "Defines an instance method in the receiver...This
P> block is evaluated using instance_eval..."

 Well, the block is not really evaluated with instance_eval


moulon% cat b.rb
#!/usr/bin/ruby
class A
   def create_method(name, &block)
      self.class.send(:define_method, name, &block)
   end
end

class B 
   def a
      A.new.create_method(:a) { def b() end }
   end
end

B.new.a
A.new.a
A.new.b
moulon% 

 if the block '{ def b() end }' is evaluated with instance_eval, ruby will
 create a singleton method, otherwise my script will work.

moulon% ./b.rb
moulon% 


Guy Decoux