Programming Ruby 3rd - new topics

• IO.foreach('file') {|line| puts line}
  
• 'abcdefghi'.scan(/abc(..)(..).*/) # => [[cd],[ef]]
  
• StringIO: use string like io
  
• Network library: socket, net/http, open-uri
  
• Fiber: fiber is like a block object
  
• Thread: use thread local variable: Thread.new(arg) {|val| ...}
  
• Thread: threads.join can wait all
  
• Thread: thread variables: can store current thread to a hash: Thread.current["mycount"] = count