From: Daniel Mendler <dmendler@...>
Date: 2009-04-16T01:13:58+09:00
Subject: Instance_eval and constants lookup rules in ruby 1.9

Hi,

what happend to the constant lookup rules in ruby 1.9? It seems
constants in blocks that are evaluated with instance_eval are looked up
only in the evaluating class but not in the scope the block was defined.

This works in Ruby 1.8 but not in 1.9:
======================================

class X
  def run(&block)
    instance_eval(&block)
  end
end

module A
  I_AM_NOT_FOUND = 666
  a = X.new
  a.run {
    puts I_AM_NOT_FOUND
  }
end

Ruby 1.8 finds the constants only if they are in the scope where the
block is defined. Why was this behaviour changed?

Daniel