diff options
Diffstat (limited to 'Doc/library/functools.rst')
| -rw-r--r-- | Doc/library/functools.rst | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/Doc/library/functools.rst b/Doc/library/functools.rst index 16a779f..8b8b1f8 100644 --- a/Doc/library/functools.rst +++ b/Doc/library/functools.rst @@ -76,7 +76,8 @@ The :mod:`functools` module defines the following functions: .. versionadded:: 3.2 -.. decorator:: lru_cache(maxsize=128, typed=False) +.. decorator:: lru_cache(user_function) + lru_cache(maxsize=128, typed=False) 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 @@ -90,6 +91,15 @@ The :mod:`functools` module defines the following functions: differ in their keyword argument order and may have two separate cache entries. + If *user_function* is specified, it must be a callable. This allows the + *lru_cache* decorator to be applied directly to a user function, leaving + the *maxsize* at its default value of 128:: + + @lru_cache + def count_vowels(sentence): + sentence = sentence.casefold() + return sum(sentence.count(vowel) for vowel in 'aeiou') + If *maxsize* is set to ``None``, the LRU feature is disabled and the cache can grow without bound. The LRU feature performs best when *maxsize* is a power-of-two. @@ -165,6 +175,9 @@ The :mod:`functools` module defines the following functions: .. versionchanged:: 3.3 Added the *typed* option. + .. versionchanged:: 3.8 + Added the *user_function* option. + .. decorator:: total_ordering Given a class defining one or more rich comparison ordering methods, this |