A fair implementation of an enum in Ruby. Inspired by Elad Meidar's article on gistflow - http://gistflow.com/posts/682-ruby-enums-approaches

enum.rb

# usage:
# FRUITS = Enum.new(:apples, :oranges)

# FRUITS[:apples] # => 0
# FRUITS[0]       # => :apples

class Enum < Hash
  def initialize(*members)
    super()
    @reverse = {}
    members.each_with_index { |m,i| self[i] = m }
  end
  def [](k)
     super || @reverse[k]
  end
  def []=(k,v)
    @reverse[v] = k
    super
  end
end