Fiber
Fibers are primitives for implementing light weight cooperative concurrency in Ruby. Basically they are a means of creating code blocks that can be paused and resumed, much like threads. The main difference is that they are never preempted and that the scheduling must be done by the programmer and not the VM.
As opposed to other stackless light weight concurrency models, each fiber comes with a small 4KB stack. This enables the fiber to be paused from deeply nested function calls within the fiber block.
When a fiber is created it will not run automatically. Rather it must be be explicitly asked to run using the Fiber#resume method. The code running inside the fiber can give up control by calling Fiber.yield in which case it yields control back to caller (the caller of the Fiber#resume).
Upon yielding or termination the Fiber returns the value of the last executed expression
yield(args, ...) → obj
Yields control back to the context that resumed the fiber, passing along any arguments that were passed to it. The fiber will resume processing at this point when resume is called next. Any arguments passed to the next resume will be the value that this Fiber.yield expression evaluates to.
http://stackoverflow.com/questions/3066703/blocks-and-yields-in-ruby
http://www.tutorialspoint.com/ruby/ruby_blocks.htm
No comments:
Post a Comment