def self.new(*members)
members = members.map { |x| x.to_sym }.freeze
str = "def initialize(*values)\n (MEMBERS.size >= values.size) or raise ArgumentError, \"too many arguments\"\n @raindrops = Raindrops.new(MEMBERS.size)\n values.each_with_index { |val,i| @raindrops[i] = values[i] }\nend\n\ndef initialize_copy(src)\n @raindrops = src.instance_variable_get(:@raindrops).dup\nend\n\ndef []=(index, value)\n @raindrops[index] = value\nend\n\ndef [](index)\n @raindrops[index]\nend\n\ndef to_hash\n ary = @raindrops.to_ary\n rv = {}\n MEMBERS.each_with_index { |member, i| rv[member] = ary[i] }\n rv\nend\n"
members.each_with_index do |member, i|
str << "def incr_#{member}; @raindrops.incr(#{i}); end; " \
"def decr_#{member}; @raindrops.decr(#{i}); end; " \
"def #{member}; @raindrops[#{i}]; end; " \
"def #{member}=(val); @raindrops[#{i}] = val; end; "
end
klass = Class.new
klass.const_set(:MEMBERS, members)
klass.class_eval(str)
klass
end