class NIO::Monitor

def initialize(io, interests, selector)
  unless io.is_a?(IO)
    if IO.respond_to? :try_convert
      io = IO.try_convert(io)
    elsif io.respond_to? :to_io
      io = io.to_io
    end
    raise TypeError, "can't convert #{io.class} into IO" unless io.is_a? IO
  end
  @io, @interests, @selector = io, interests, selector
  @closed = false
end