| 12
 3
 4
 5
 6
 7
 8
 9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 
 | module Kernel
  def n
    self.class.name
  end
end
class C
  def b
    binding
  end
  protected
  def foo
    puts 'ok'
  end   
end
class X
  def b
    binding
  end
end
class D < C
  def b
    binding
  end
end
$sc = C.new
class << $sc
  def b
    binding
  end
end
$sd = D.new
class << $sd
  def b
    binding
  end
end
$c,$d,$x = C.new,D.new,X.new
['c', 'd', 'sc', 'sd'].each do |target|
  [$c, $d, $sc, $sd, $x].each do |cls|
    print "#{target} in #{cls.n}: "
    eval("$#{target}.foo", cls.b) rescue p $!
  end
end
 |