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-rw-r--r--Lib/_threading_local.py122
1 files changed, 0 insertions, 122 deletions
diff --git a/Lib/_threading_local.py b/Lib/_threading_local.py
index b006d76c4e2..0b9e5d3bbf6 100644
--- a/Lib/_threading_local.py
+++ b/Lib/_threading_local.py
@@ -4,128 +4,6 @@
class. Depending on the version of Python you're using, there may be a
faster one available. You should always import the `local` class from
`threading`.)
-
-Thread-local objects support the management of thread-local data.
-If you have data that you want to be local to a thread, simply create
-a thread-local object and use its attributes:
-
- >>> mydata = local()
- >>> mydata.number = 42
- >>> mydata.number
- 42
-
-You can also access the local-object's dictionary:
-
- >>> mydata.__dict__
- {'number': 42}
- >>> mydata.__dict__.setdefault('widgets', [])
- []
- >>> mydata.widgets
- []
-
-What's important about thread-local objects is that their data are
-local to a thread. If we access the data in a different thread:
-
- >>> log = []
- >>> def f():
- ... items = sorted(mydata.__dict__.items())
- ... log.append(items)
- ... mydata.number = 11
- ... log.append(mydata.number)
-
- >>> import threading
- >>> thread = threading.Thread(target=f)
- >>> thread.start()
- >>> thread.join()
- >>> log
- [[], 11]
-
-we get different data. Furthermore, changes made in the other thread
-don't affect data seen in this thread:
-
- >>> mydata.number
- 42
-
-Of course, values you get from a local object, including a __dict__
-attribute, are for whatever thread was current at the time the
-attribute was read. For that reason, you generally don't want to save
-these values across threads, as they apply only to the thread they
-came from.
-
-You can create custom local objects by subclassing the local class:
-
- >>> class MyLocal(local):
- ... number = 2
- ... def __init__(self, /, **kw):
- ... self.__dict__.update(kw)
- ... def squared(self):
- ... return self.number ** 2
-
-This can be useful to support default values, methods and
-initialization. Note that if you define an __init__ method, it will be
-called each time the local object is used in a separate thread. This
-is necessary to initialize each thread's dictionary.
-
-Now if we create a local object:
-
- >>> mydata = MyLocal(color='red')
-
-Now we have a default number:
-
- >>> mydata.number
- 2
-
-an initial color:
-
- >>> mydata.color
- 'red'
- >>> del mydata.color
-
-And a method that operates on the data:
-
- >>> mydata.squared()
- 4
-
-As before, we can access the data in a separate thread:
-
- >>> log = []
- >>> thread = threading.Thread(target=f)
- >>> thread.start()
- >>> thread.join()
- >>> log
- [[('color', 'red')], 11]
-
-without affecting this thread's data:
-
- >>> mydata.number
- 2
- >>> mydata.color
- Traceback (most recent call last):
- ...
- AttributeError: 'MyLocal' object has no attribute 'color'
-
-Note that subclasses can define slots, but they are not thread
-local. They are shared across threads:
-
- >>> class MyLocal(local):
- ... __slots__ = 'number'
-
- >>> mydata = MyLocal()
- >>> mydata.number = 42
- >>> mydata.color = 'red'
-
-So, the separate thread:
-
- >>> thread = threading.Thread(target=f)
- >>> thread.start()
- >>> thread.join()
-
-affects what we see:
-
- >>> mydata.number
- 11
-
->>> del mydata
"""
from weakref import ref