From: Dave Thomas <Dave@...>
Date: 2001-02-23T10:33:06+09:00
Subject: [ruby-talk:11358] Re: binding to callers namespace.

"Joseph McDonald" <joe@vpop.net> writes:

> Am I using caller wrong here?

'fraid so.  Caller returns an array containing the call stack, not the 
object that is the caller.

You _could_ do something similar to what you want though, using
eval. The code below shows two ways to get the binding: both involve
cooperation on behalf of the caller:

     class Object
       public :binding
     end

     class Display
       def initialize(aBinding)
         @binding = aBinding
       end
       def render
         puts "secret is #{eval '@secret', @binding } var is #{eval 'var',@binding}"
       end
     end

     class Display2
       def render(&binding)
         puts "secret is #{eval '@secret', binding } var is #{eval 'var', binding}"
       end
     end

     class Demo 
       def initialize(n) 
         @secret = n 
       end 

       def display
         var = "asdf"
         d = Display.new(binding)
         d.render # want to give it access to @secret and "var"

         d = Display2.new
         d.render {}
       end
     end 

     k1 = Demo.new(99) 
     k1.display


However, you might want to think about alternative designs to get the
same effect... this is going to get messy pretty quickly :)


Regards


Dave