how to find the size of a binding - less is good - can i be selective

proc_binding_size.rb

str = "hello"
#c=0
#p = Proc.new { str.size }
#p.binding.eval("ObjectSpace.each_object { c +=1 }")

def enclose_binding(*attr)
  p = Proc.new { attr[0].size }

  code = <<-CODE
  class_ivars = self.class.instance_variables || []
  ivars = self.instance_variables
  puts "ivars: #{ivars.inspect} | #{ivars.class}" #why is ivars not refined
  cvars = (self.class_variables || []) if self.respond_to?(:class_variables)
  class_cvars = (self.class.class_variables || []) if self.class.respond_to?(:class_variables)
  vars = class_ivars + ivars + cvars + class_cvars + global_variables + local_variable
  puts vars
  CODE

  #does not work - i do not think the ObjectSpace is in the scope of the binding
  # p.binding.eval("c=0;ObjectSpace.each_object { c +=1 }") 
  p.binding.eval(code)
end

enclose_binding(str)