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Added section on monkey patching.
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‎index.html‎

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@@ -57,6 +57,7 @@ <h3 class="author">
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<li><a href="#greenlet-state">Greenlet State</a></li>
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<li><a href="#program-shutdown">Program Shutdown</a></li>
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<li><a href="#timeouts">Timeouts</a></li>
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<li><a href="#monkeypatching">Monkeypatching</a></li>
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</ul>
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</li>
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<li><a href="#data-structures">Data Structures</a><ul>
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Task 8 done
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Asynchronous:
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</pre></code></p>
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<p>In the synchronous case all the tasks are run sequentially,
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which results in the main programming <em>blocking</em> (
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Thread 2 timed out
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</pre></code></p>
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<h2 id="monkeypatching">Monkeypatching</h2>
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<p>Alas we come to dark corners of Gevent. I've avoided mentioning
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monkey patching up until now to try and motivate the powerful
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coroutine patterns but the time has come to discuss the dark arts
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of monkey-patching. If you noticed above we invoked the commnad
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<code>monkey.patch_socket()</code>. This is a purely side-effectful command to
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modify the standard library's socket library</p>
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<pre>
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<code class="python">import socket
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print( socket.socket )
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print "After monkey patch"
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from gevent import monkey
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monkey.patch_socket()
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print( socket.socket )
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import select
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print select.select
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monkey.patch_select()
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print "After monkey patch"
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print( select.select )
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</code>
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</pre>
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<pre>
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<code class="python">class 'socket.socket'
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After monkey patch
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class 'gevent.socket.socket'
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After monkey patch
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built-in function select
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function select at 0x1924de8
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</code>
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</pre>
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<p>Python's runtime allows for most objects to be modified at runtime
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including modules, classes, and even functions. This is generally an
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astoudingly bad idea since it creates an "implicit side-effect" that is
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most often extremely difficult to debug if problems occur, nevertheless
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in extreme situations where a library needs to alter the fundamental
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behavior of Python itself monkey patches can be used. In this case gevent
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is capable of patching most of the blocking system calls in the standard
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library including those in <code>socket</code>, <code>ssl</code>, <code>threading</code> and
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<code>select</code> modules to instead behave cooperatively.</p>
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<p>For example, the Redis python bindings normally uses regular tcp
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sockets to communicate with the <code>redis-server</code> instance. Simply
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by invoking <code>gevent.monkey.patch_all()</code> we can make the redis
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bindings schedule requests cooperatively and work with the rest
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of our gevent stack.</p>
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<p>This lets us integrate libraries that would not normally work with
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gevent without ever writing a single line of code. While monkey-patching
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is still evil, in this case it is a "usefull evil".</p>
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<h1 id="data-structures">Data Structures</h1>
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<h2 id="events">Events</h2>
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<p>Events are a form of asynchronous communication between
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<p></code>
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<pre><code class="python">
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Size of group 3
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Hello from Greenlet 41900624
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Hello from Greenlet 42121488
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Size of group 3
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Hello from Greenlet 41900944
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Hello from Greenlet 42119248
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Size of group 3
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Hello from Greenlet 41899024
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Hello from Greenlet 42120208
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Ordered
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('task', 0)
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('task', 1)

‎tutorial.md‎

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]]]
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[[[end]]]
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## Monkeypatching
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Alas we come to dark corners of Gevent. I've avoided mentioning
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monkey patching up until now to try and motivate the powerful
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coroutine patterns but the time has come to discuss the dark arts
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of monkey-patching. If you noticed above we invoked the commnad
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``monkey.patch_socket()``. This is a purely side-effectful command to
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modify the standard library's socket library
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<pre>
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<code class="python">import socket
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print( socket.socket )
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print "After monkey patch"
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from gevent import monkey
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monkey.patch_socket()
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print( socket.socket )
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import select
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print select.select
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monkey.patch_select()
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print "After monkey patch"
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print( select.select )
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</code>
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</pre>
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<pre>
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<code class="python">class 'socket.socket'
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After monkey patch
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class 'gevent.socket.socket'
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built-in function select
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After monkey patch
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function select at 0x1924de8
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</code>
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</pre>
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Python's runtime allows for most objects to be modified at runtime
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including modules, classes, and even functions. This is generally an
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astoudingly bad idea since it creates an "implicit side-effect" that is
554+
most often extremely difficult to debug if problems occur, nevertheless
555+
in extreme situations where a library needs to alter the fundamental
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behavior of Python itself monkey patches can be used. In this case gevent
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is capable of patching most of the blocking system calls in the standard
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library including those in ``socket``, ``ssl``, ``threading`` and
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``select`` modules to instead behave cooperatively.
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For example, the Redis python bindings normally uses regular tcp
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sockets to communicate with the ``redis-server`` instance. Simply
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by invoking ``gevent.monkey.patch_all()`` we can make the redis
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bindings schedule requests cooperatively and work with the rest
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of our gevent stack.
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This lets us integrate libraries that would not normally work with
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gevent without ever writing a single line of code. While monkey-patching
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is still evil, in this case it is a "usefull evil".
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# Data Structures
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## Events

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