From 9f0ab9f5649b9b6ee54a023e83417f244b4665a0 Mon Sep 17 00:00:00 2001 From: Raymond Hettinger Date: Sun, 29 Apr 2012 14:55:27 -0700 Subject: [PATCH] Factor out shared variables. --- Lib/functools.py | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/Lib/functools.py b/Lib/functools.py index 1e7795f7920..af0864f2268 100644 --- a/Lib/functools.py +++ b/Lib/functools.py @@ -167,18 +167,20 @@ def lru_cache(maxsize=100, typed=False): # The internals of the lru_cache are encapsulated for thread safety and # to allow the implementation to change (including a possible C version). + # Constants shared by all lru cache instances: + kwd_mark = (object(),) # separate positional and keyword args + sentinel = object() # unique object used to signal cache misses + _len = len # localize the global len() function + PREV, NEXT, KEY, RESULT = 0, 1, 2, 3 # names for the link fields + def decorating_function(user_function): cache = {} hits = misses = 0 - kwd_mark = (object(),) # separate positional and keyword args cache_get = cache.get # bound method to lookup a key or return None - sentinel = object() # unique object used with cache_get - _len = len # localize the global len() function lock = Lock() # because linkedlist updates aren't threadsafe root = [] # root of the circular doubly linked list root[:] = [root, root, None, None] # initialize by pointing to self - PREV, NEXT, KEY, RESULT = 0, 1, 2, 3 # names for the link fields def make_key(args, kwds, typed, tuple=tuple, sorted=sorted, type=type): # build a cache key from positional and keyword args