State machine in Ruby using Fibers? -

I'm trying to get a handle on the new fiber class in Ruby 1.9 and I It is read that one of the more common applications for fiber (and coroutines) is in state machines

Unfortunately my fiber -foo is not much , So I used to hope that one of you could show me a simple statemashine example in Ruby using fiber << P>

thanks :)

shows you how to feed one that makes another feed

< P> AAAB (on input x) => AAB (in each) is dividing each person into its fiber. [A, A, A, B] should have its own fiber, and close the input until it reaches the end)