names=DEFAULT_INPUT
visibility=public
kind=added

--- $DEFAULT_INPUT -> IO

[[m:$<]] の別名
  
  require "English"
  while line = $DEFAULT_INPUT.gets
    p line
  end
  # end of sample.rb

  ruby sample.rb < /etc/passwd 
  # => "hoge:x:500:501::/home/hoge:/bin/bash\n"
       ...

