# File lib/eventmachine.rb, line 891
891:         def self::open_datagram_socket address, port, handler=nil, *args
892:                 klass = if (handler and handler.is_a?(Class))
893:                   raise ArgumentError, 'must provide module or subclass of EventMachine::Connection' unless Connection > handler
894:                         handler
895:                 else
896:                         Class.new( Connection ) {handler and include handler}
897:                 end
898: 
899:     arity = klass.instance_method(:initialize).arity
900:     expected = arity >= 0 ? arity : -(arity + 1)
901:     if (arity >= 0 and args.size != expected) or (arity < 0 and args.size < expected)
902:       raise ArgumentError, "wrong number of arguments for #{klass}#initialize (#{args.size} for #{expected})"
903:     end
904: 
905:                 s = open_udp_socket address, port
906:                 c = klass.new s, *args
907:                 @conns[s] = c
908:                 block_given? and yield c
909:                 c
910:         end