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Re-commit r83327 now that the release is done.

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Georg Brandl 2010-07-31 18:09:23 +00:00
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Doc/library/functools.rst
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@ -37,6 +37,57 @@ The :mod:`functools` module defines the following functions:
.. versionadded:: 3.2
.. decorator:: lfu_cache(maxsize)
Decorator to wrap a function with a memoizing callable that saves up to the
*maxsize* most frequent calls. It can save time when an expensive or I/O
bound function is periodically called with the same arguments.
The *maxsize* parameter defaults to 100. Since a dictionary is used to cache
results, the positional and keyword arguments to the function must be
hashable.
The wrapped function is instrumented with two attributes, :attr:`hits`
and :attr:`misses` which count the number of successful or unsuccessful
cache lookups. These statistics are helpful for tuning the *maxsize*
parameter and for measuring the cache's effectiveness.
The wrapped function also has a :attr:`clear` attribute which can be
called (with no arguments) to clear the cache.
A `LFU (least frequently used) cache
<http://en.wikipedia.org/wiki/Cache_algorithms#Least-Frequently_Used>`_
is indicated when the pattern of calls does not change over time, when
more the most common calls already seen are the best predictors of the
most common upcoming calls.
.. versionadded:: 3.2
.. decorator:: lru_cache(maxsize)
Decorator to wrap a function with a memoizing callable that saves up to the
*maxsize* most recent calls. It can save time when an expensive or I/O bound
function is periodically called with the same arguments.
The *maxsize* parameter defaults to 100. Since a dictionary is used to cache
results, the positional and keyword arguments to the function must be
hashable.
The wrapped function is instrumented with two attributes, :attr:`hits`
and :attr:`misses` which count the number of successful or unsuccessful
cache lookups. These statistics are helpful for tuning the *maxsize*
parameter and for measuring the cache's effectiveness.
The wrapped function also has a :attr:`clear` attribute which can be
called (with no arguments) to clear the cache.
A `LRU (least recently used) cache
<http://en.wikipedia.org/wiki/Cache_algorithms#Least_Recently_Used>`_
is indicated when the pattern of calls changes over time, such as
when more recent calls are the best predictors of upcoming calls.
.. versionadded:: 3.2
.. decorator:: total_ordering
Given a class defining one or more rich comparison ordering methods, this