class RDoc::Markup::Attribute

def self.as_string(bitmap)
  return "none" if bitmap.zero?
  res = []
  @@name_to_bitmap.each do |name, bit|
    res << name if (bitmap & bit) != 0
  end
  res.join(",")
end

def self.bitmap_for(name)
  bitmap = @@name_to_bitmap[name]
  unless bitmap then
    bitmap = @@next_bitmap
    @@next_bitmap <<= 1
    @@name_to_bitmap[name] = bitmap
  end
  bitmap
end

def self.each_name_of(bitmap)
  @@name_to_bitmap.each do |name, bit|
    next if bit == SPECIAL
    yield name.to_s if (bitmap & bit) != 0
  end
end