More on this: https://robm.me.uk/ruby/2013/11/20/ruby-enp.html https://robm.me.uk/ruby/2013/11/20/ruby-enp.html https://robm.me.uk/ruby/2013/12/03/argf-ruby.h

More on this: https://robm.me.uk/ruby/2013/11/20/ruby-enp.html https://robm.me.uk/ruby/2013/11/20/ruby-enp.html https://robm.me.uk/ruby/2013/12/03/argf-ruby.html https://robm.me.uk/ruby/2013/12/03/argf-ruby.html https://robm.me.uk/ruby/2015/10/31/dollar-underscore.html https://robm.me.uk/ruby/2015/10/31/dollar-underscore.html and his book: https://pragprog.com/book/rmtpruby/text-processing-with-ruby https://pragprog.com/book/rmtpruby/text-processing-with-ruby