编辑“︁Stackless Python”︁

{{Infobox software
| name = Stackless Python
| logo = 
| screenshot = 
| caption = 
| collapsible = 
| author = Christian Tismer
| developer = Anselm Kruis
| released = {{Start date and age|1998}}
| latest release version = v3.8.1-slp
| latest release date = {{Start date and age|2021|08|12}}
| latest preview version = 
| latest preview date = 
| programming language = [[C语言|C]], [[Python]]
| operating system = [[Linux]], [[Microsoft Windows|Windows]]
| platform = 
| size = 
| language = 
| genre = [[解释器]]
| license = [[Python软件基金会许可证]]
| website = 
}}

'''Stackless Python'''或称简称'''Stackless'''，是一个[[Python|Python编程语言]]解释器，这么称呼的原因是它避免了依赖[[C语言|C]][[调用栈]]为自己的堆栈。在实际中，Stackless Python使用了C堆栈，但是这个堆栈在函数调用之间是被清除的<ref>{{Cite web |url=https://www.youtube.com/watch?v=pDkrkP0yf70 |title=存档副本 |accessdate=2020-09-30 |archive-date=2020-08-29 |archive-url=https://web.archive.org/web/20200829130130/https://www.youtube.com/watch?v=pDkrkP0yf70 |dead-url=no }}</ref>。Stackless Python的最突出特征是{{le|微线程|Microthread}}，它避免了与操作系统[[线程]]有关的大量开销。在Python特征之外，Stackless还增加了[[协程]]、通信[[通道 (编程)|通道]]和任务[[序列化]]。

==设计==
对于Stackless Python，一个运行的程序被分解成微线程，由语言解释器自身而非操作系统[[内核]]管理，[[上下文切换]]和[[调度 (计算机)|任务调度]]纯粹在解释器内完成，因而可以被视作是一种形式的[[绿色线程]]。微线程管理在同一个CPU核心上一个程序的不同子任务的执行，Stackless Python不移除Python的[[全局解释器锁]], 也不使用多线程或多进程。所以它只允许在一个共享CPU核心上的[[协作式多任务]]而非[[并行计算|并行]]，最初不能获得而现在有了某种形式的抢占<ref>{{cite web |url=https://bitbucket.org/stackless-dev/stackless/wiki/Home |title=About Stackless |quote=a round robin scheduler is built in. It can be used to schedule tasklets either cooperatively or preemptively. |accessdate=26 August 2016 |archive-date=2020-06-23 |archive-url=https://web.archive.org/web/20200623233250/https://bitbucket.org/stackless-dev/stackless/wiki/Home |dead-url=no }}</ref>。

由于相当数量的源代码变更，Stackless Python不能在现存的Python安装上作为一个[[插件|扩展]]或[[函式库|库]]来安装。它自身是完整的Python发行。大多数的Stackless Python的特征也在[[PyPy]]中实现了，它是{{le|自我寄宿|Self-hosting (compilers)}}的Python解释器和[[即时编译|JIT编译器]]<ref>{{cite web|url=http://pypy.readthedocs.org/en/latest/stackless.html|title=Application-level Stackless features — PyPy documentation|website=pypy.readthedocs.org|accessdate=2020-09-30|archive-date=2016-04-13|archive-url=https://web.archive.org/web/20160413211003/https://pypy.readthedocs.org/en/latest/stackless.html|dead-url=no}}</ref>。

==使用==
尽管整个Stackless Python是一个独立发行，它的上下文切换功能已经成功的打包为叫做greenlet的[[CPython]]扩展<ref>{{cite web|url=http://greenlet.readthedocs.org/en/latest/|title=greenlet: Lightweight concurrent programming — greenlet 0.4.0 documentation|website=greenlet.readthedocs.org|accessdate=2020-09-30|archive-date=2016-04-16|archive-url=https://web.archive.org/web/20160416091857/http://greenlet.readthedocs.org/en/latest/|dead-url=no}}</ref>。它被用在很多库，比如gevent<ref>{{cite web|url=http://www.gevent.org|title=What is gevent? — gevent 1.3.0.dev0 documentation|website=www.gevent.org|accessdate=2020-12-09|archive-date=2020-09-16|archive-url=https://web.archive.org/web/20200916085654/http://www.gevent.org/|dead-url=no}}</ref>，用来提供CPython的[[绿色线程]]解决方案。Python现在已经接受了对绿色线程的原生解决方案：[[async/await]]。

Stackless Python广泛的使用在大规模多玩家在线游戏{{le|Eve Online|Eve Online}}的实现和{{le|IronPort|IronPort}}的邮件平台。

==引用==
{{Reflist|2}}

==参閱==
{{Portal|自由软件}}
* [[Erlang]]
* [[Limbo (程式语言)]]
* [[Go語言|Go]]
* {{le|SCOOP (软件)|SCOOP (software)}}

==外部链接==
* Stackless Python Documentation for: [https://stackless.readthedocs.io/en/3.7-slp/stackless-python.html 3.7-slp]{{Wayback|url=https://stackless.readthedocs.io/en/3.7-slp/stackless-python.html |date=20190331231737 }}, [https://stackless.readthedocs.io/en/3.6-slp/stackless-python.html 3.6-slp]{{Wayback|url=https://stackless.readthedocs.io/en/3.6-slp/stackless-python.html |date=20190209180414 }}, [https://stackless.readthedocs.io/en/3.5-slp/stackless-python.html 3.5-slp]{{Wayback|url=https://stackless.readthedocs.io/en/3.5-slp/stackless-python.html |date=20190331231741 }}, [https://stackless.readthedocs.io/en/3.4-slp/stackless-python.html 3.4-slp]{{Wayback|url=https://stackless.readthedocs.io/en/3.4-slp/stackless-python.html |date=20190331231743 }}, [https://stackless.readthedocs.io/en/2.7-slp/stackless-python.html 2.7-slp]{{Wayback|url=https://stackless.readthedocs.io/en/2.7-slp/stackless-python.html |date=20190331231800 }}
* {{GitHub|stackless-dev/stackless}}
* [http://harkal.sylphis3d.com/2005/08/10/multithreaded-game-scripting-with-stackless-python/ Multithreaded Game Scripting with Stackless Python]{{Wayback|url=http://harkal.sylphis3d.com/2005/08/10/multithreaded-game-scripting-with-stackless-python/ |date=20170702173643 }} by Harry Kalogirou
* [https://web.archive.org/web/20121108011701/http://zope.stackless.com/spcpaper.htm Continuations and Stackless Python] by Christian Tismer
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{{Python|state=collapsed}}

[[Category:并发计算]]
[[Category:Python]]
[[Category:采用Python软件基金会许可证的软件]]