tips on EventMachine::start_server

gistfile1.rb

# Following comments on eventmachine.rb - V1.0.0-beta4.1

# at line:502
def self.start_server server, port=nil, handler=nil, *args, &block
  begin
    port = Integer(port)
  rescue ArgumentError, TypeError
    # there was no port, so server must be a unix domain socket
    # the port argument is actually the handler, and the handler is one of the args
    args.unshift handler if handler
    handler = port
    port = nil
  end if port

  klass = klass_from_handler(Connection, handler, *args)

  s = if port
  			# ===============================================================
  			# all secret is in [pure_ruby.rb] file.
  			# start_tcp_server() is a singlton method of EventMachine module:
  			#       def start_tcp_server host, port
		    #         (s = EvmaTCPServer.start_server host, port) or raise "no acceptor"
		    #         s.uuid
		    #       end
  			# EvmaTCPServer is a class under EventMachine, 
  			# start_server() is a singleton method, see its definition
  			#       class EvmaTCPServer < Selectable
  			#				  class << self
		    #			      def start_server host, port
				#			        sd = Socket.new( Socket::AF_INET, Socket::SOCK_STREAM, 0 )
				#			        sd.setsockopt( Socket::SOL_SOCKET, Socket::SO_REUSEADDR, true )
				#			        sd.bind( Socket.pack_sockaddr_in( port, host ))
				#			        sd.listen( 50 ) # 5 is what you see in all the books. Ain't enough.
				#             # EvmaTCPServer.new(sd) call EvmaTCPServer.initialize(io), 
				#             # which inheritted from class Selectable,
				#             # and set the socket fd attribute.
				#			        EvmaTCPServer.new sd
				#			      end
				#	        end
				#	      end
  			# Hah, 
  			# ===============================================================
        start_tcp_server server, port
      else
        start_unix_server server
      end
  @acceptors[s] = [klass,args,block]
  # ================================================================
  # returnd variable <s> is returned by EvmaTCPServer#start_tcp_server, 
  # which is a uuid, increase from 0
  # ================================================================
  s
end

# at line:1459
def self.klass_from_handler(klass = Connection, handler = nil, *args)
  klass = if handler and handler.is_a?(Class)
    raise ArgumentError, "must provide module or subclass of #{klass.name}" unless klass >= handler
    handler
  # ===============================================================
  # Here, means that handler is a module
  # then a anoymous class initilized which mix-in handler module
  # and set :EM_CONNECTION_CLASS const to this new anonymous class
  # ===============================================================
  elsif handler
    begin
      handler::EM_CONNECTION_CLASS
    rescue NameError
      handler::const_set(:EM_CONNECTION_CLASS, Class.new(klass) {include handler})
    end
  else
    klass
  end

  arity = klass.instance_method(:initialize).arity
  expected = arity >= 0 ? arity : -(arity + 1)
  if (arity >= 0 and args.size != expected) or (arity < 0 and args.size < expected)
    raise ArgumentError, "wrong number of arguments for #{klass}#initialize (#{args.size} for #{expected})"
  end
  klass
end