You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: select.rb
    path of file: ./repos/concurrent-ruby/examples/a-tour-of-go-channels
    
    the code of the file until where you have to start completion: #!/usr/bin/env ruby

$: << File.expan
    
def fibonacci(c, quit)
  x, y = 0, 1
  loop do
    Channel.select do |s|
      s.case(c, :<<, x) { x, y = y, x+y; x } # alias for `s.put`
      s.case(quit, :~) do                    # alias for `s.take`
        puts 'quit'
        return
      end
    end
  end
end