# File lib/rubygems/specification.rb, line 240
    def self.attribute_alias_singular(singular, plural)
      define_method("#{singular}=") { |val|
        send("#{plural}=", [val])
      }
      define_method("#{singular}") { 
        val = send("#{plural}")
        val.nil? ? nil : val.first
      }
    end