def after_or_asgn
      variable = variable_stack.pop.first
      value    = value_stack.pop.first

      if variable and value
        conditional_assignment(variable, value, false)
      end
    end
def after_or_asgn
      variable = variable_stack.pop.first
      value    = value_stack.pop.first

      if variable and value
        conditional_assignment(variable, value, false)
      end
    end
Processes an `or` assignment in the form of `variable ||= value`.