Monkey patch for speedup date/time parsing

gistfile1.rb

class Date
  module Format
    class Bag
      A_FIELDS = %w{year mon mday hour min sec sec_fraction offset zone wday}
      for fld in A_FIELDS + %w{_comp}
	attr_accessor fld.to_sym
      end
      
      to_hash = A_FIELDS.map{|fld| "res[:#{fld}] = @#{fld} unless @#{fld}.nil?"}.join("\n")
      class_eval <<-"END"
	def to_hash
	  res = @elem.empty? ? {} : @elem.reject{|k,v| /\A_/ =~ k.to_s || v.nil? }
          #{to_hash}
	  res 
	end
      END
    end
  end
end

It seems that it is not need for ruby 1.9.3 (future versions). But it will help with <=1.9.2.