class Object
  def singleton_class
    class << self
      self
    end
  end
end

[String, Array, Hash].each do |klass|
    case klass
    when String.singleton_class
        puts "String!"
    when Array.singleton_class
        puts "Array!"
    when Hash.singleton_class
        puts "Hash!"
    else
        puts "I don't know: #{klass}"
    end
end

Hrm it would be nice to have some kind of voting system for feature 
requests
http://redmine.ruby-lang.org/issues/show/1082
-- 
Posted via http://www.ruby-forum.com/.