From: ko1@...
Date: 2014-10-23T01:08:29+00:00
Subject: [ruby-core:65863] [ruby-trunk - Feature #10344] [PATCH] Implement	Fiber#raise

Issue #10344 has been updated by Koichi Sasada.


Knut Franke wrote:
> > I understand this feature helps some libraries. But I can't understand why it is important.
> 
> Without Fiber#raise, libraries need to use some rather inelegant and inefficient workarounds (wrapping or tagging exceptions, wrapping Fiber.yield etc).

I understand.

> Also, having Thread#raise arguably leads one to expect the same functionality in Fiber. I'm not sure whether the feature qualifies as "important", but I still think it is worth including.

I don't expect there is Fiber#raise. Fiber and Thread are different.

> > Basically, I want to recommend strongly that using Fiber as semi-croutine, ristricted feature.
> 
> I think [Consumer](http://nome.github.io/coroutines/Consumer.html) is an example of a semi-coroutine (in the sense that it uses Fiber.yield, not Fiber#transfer) that benefits from having Fiber#raise.

Interesting. I don't know details of this library. Could you explain why it is important in this library?


----------------------------------------
Feature #10344: [PATCH] Implement Fiber#raise
https://bugs.ruby-lang.org/issues/10344#change-49598

* Author: Knut Franke
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
----------------------------------------
While it is possible to implement this in pure Ruby (by wrapping Fiber.yield and Fiber#resume), this feels like a low-level feature that ought to be provided out of the box. Also, the C implementation is more straight-forward, and more efficient. Unfortunately, it is not quite possible to implement this as a C extension module (without resorting to wrappers again); cf. the change to make_passing_arg().

Example usage:

~~~
fib = Fiber.new do
  counter = 0
  loop { counter += Fiber.yield }
  counter
end
fib.resume
fib.resume 10
fib.resume 100
fib.raise StopIteration # => 110
~~~

---Files--------------------------------
0001-Implement-Fiber-raise.patch (4.12 KB)
0001-Implement-Fiber-raise.patch (3.51 KB)
0001-Implement-Fiber-raise-in-ext-fiber.patch (3.6 KB)


-- 
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