Working examples of EM::Iterator

Question

Does anyone have any working examples of EM::Iterator? The only examples I can find seem to be copies of (or point back to):

http://yardoc.org/docs/eventmachine-eventmachine/EventMachine/Iterator

I don't see any instances of EM::Iterator in EventMachine's Rdoc, so I'm not sure if it's an old class that has been removed or not. I generally get the following error when I try to use EM::Iterator:

NameError: uninitialized constant EventMachine::Iterator

Thanks!

Answer 1

The problem is that the latest released EventMachine version is 0.12.10, which is now 10 months old. EM::Iterator appears to have been added to the code base after that release; to utilize it, you will need to be using the development version of EventMachine.

The following worked for me:

$ git clone git://github.com/eventmachine/eventmachine.git
$ cd eventmachine
$ irb -Ilib -reventmachine
irb(main):001:0> EM.run do
irb(main):002:1*   EM::Iterator.new(0..10, 2).each do |num, iter|
irb(main):003:2*     puts num
irb(main):004:2>     EM.add_timer(1) { iter.next }
irb(main):005:2>   end
irb(main):006:1> end
...

There are also some slides relating to EM::Iterator in Aman Gupta's excellent presentation EventMachine: scalable non-blocking i/o in ruby, pages 46-50.