Readline-NG is /not/ a drop in replacement for readline.

It addresses a very specific need I had inside a twitter client, but hopefully it's of use to someone else, too.

Readline relies on being able to poll for input often, leading to a hideously inefficient event loop, but generally

reader = ReadlineNG::Reader.new
loop do
  reader.tick
  reader.each_line do |line|
    # Handle full line of input
    reader.puts_above("user input #{line}")
  end
end