From: Paul Brannan <pbrannan@...>
Date: 2004-05-05T05:51:09+09:00
Subject: Re: Lazy evaluation

On Sat, May 01, 2004 at 03:45:04AM +0900, Michael Neumann wrote:
> Any comments or suggestions?

I'm not suggesting that anyone actually do this, but I have a lazily-
evaluated object that looks something like this:

  class LazyFoo
    def method_missing(*args, &block)
      $foo = Foo.new
      $foo.__send__(*args, &block)
    end

    Kernel.instance_methods.each do |m|
      next if m == '__send__'
      next if m == '__id__'
      eval <<-END
        def #{m}(*args, &block)
          method_missing(:#{m}, *args, &block)
        end
      END
    end
  end

  $foo = LazyFoo.new

Obviously this only works with global variables, and it doesn't work if
you pass the variable around.  IMO Object#become is a much cleaner
solution, and while there are some limitations with every Object#become
I've seen thus far for Ruby 1.6 and 1.8, I hope that we will have a
clean implementation of Object#become in a future version of Ruby, so
that we can have nice lazy evaluation without using delegates.

Paul