Comments on: Learning Ruby – Day 2 http://garrickvanburen.com/archive/learning-ruby-day-2 User Experience Strategy, Ruby and Rails Web App Development Sat, 20 Mar 2010 01:04:57 +0000 http://wordpress.org/?v=2.8.4 hourly 1 By: flgr http://garrickvanburen.com/archive/learning-ruby-day-2/comment-page-1#comment-34 flgr Mon, 04 Apr 2005 23:27:09 +0000 http://garrickvanburen.com/archive/learning-ruby-day-2#comment-34 And while we're talking about debugging and asking objects what they do: I think that talking with your objects is an excellent way of debugging them. Therefore I decided to write the ruby-breakpoint library (see http://ruby-breakpoint.rubyforge.org/) which lets you spawn an IRB shell at any point of your code and then investigate what happened. You can even hot-fix your code at run-time and there is guys who are using this as a maintenance hatch into their code. It comes as a part of RubyOnRails but is also available as a stand-alone library. And while we’re talking about debugging and asking objects what they do: I think that talking with your objects is an excellent way of debugging them. Therefore I decided to write the ruby-breakpoint library (see http://ruby-breakpoint.rubyforge.org/) which lets you spawn an IRB shell at any point of your code and then investigate what happened. You can even hot-fix your code at run-time and there is guys who are using this as a maintenance hatch into their code.

It comes as a part of RubyOnRails but is also available as a stand-alone library.

]]> By: Garrick Van Buren http://garrickvanburen.com/archive/learning-ruby-day-2/comment-page-1#comment-27 Garrick Van Buren Wed, 30 Mar 2005 16:56:21 +0000 http://garrickvanburen.com/archive/learning-ruby-day-2#comment-27 Rik, thanks for the clarification and the example. Rik, thanks for the clarification and the example.

]]> By: Rik Hemsley http://garrickvanburen.com/archive/learning-ruby-day-2/comment-page-1#comment-26 Rik Hemsley Wed, 30 Mar 2005 09:51:53 +0000 http://garrickvanburen.com/archive/learning-ruby-day-2#comment-26 Time.now + Time.now isn't adding two strings together. It's adding two objects of class Time together. irb(main):001:0> Time.now.class => Time You can't add two times together in Ruby because you can't do it in real life: times aren't numbers. You can, of course, subtract one time from another, to give a difference in seconds. irb(main):001:0> t = Time.now => Wed Mar 30 10:50:44 GMT0:00 2005 irb(main):002:0> t2 = t + 20 => Wed Mar 30 10:51:04 GMT0:00 2005 irb(main):003:0> t2 - t => 20.0 Time.now + Time.now isn’t adding two strings together. It’s adding two objects of class Time together.

irb(main):001:0> Time.now.class
=> Time

You can’t add two times together in Ruby because you can’t do it in real life: times aren’t numbers.

You can, of course, subtract one time from another, to give a difference in seconds.

irb(main):001:0> t = Time.now
=> Wed Mar 30 10:50:44 GMT0:00 2005
irb(main):002:0> t2 = t + 20
=> Wed Mar 30 10:51:04 GMT0:00 2005
irb(main):003:0> t2 – t
=> 20.0

]]>