# File lib/rdoc/context.rb, line 447
  def add_module_alias from, name, file
    return from if @done_documenting

    to_name = child_name(name)

    # if we already know this name, don't register an alias:
    # see the metaprogramming in lib/active_support/basic_object.rb,
    # where we already know BasicObject as a class when we find
    # BasicObject = BlankSlate
    return from if RDoc::TopLevel.find_class_or_module(to_name)

    if from.module? then
      RDoc::TopLevel.modules_hash[to_name] = from
      @modules[name] = from
    else
      RDoc::TopLevel.classes_hash[to_name] = from
      @classes[name] = from
    end

    # HACK: register a constant for this alias:
    # constant value and comment will be updated after,
    # when the Ruby parser adds the constant
    const = RDoc::Constant.new name, nil, ''
    const.record_location file
    const.is_alias_for = from
    add_constant const

    from
  end