44 lines
974 B
Python
44 lines
974 B
Python
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import collections
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class Cache:
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def __init__(self, maxlen):
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self.maxlen = maxlen
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self.cache = collections.OrderedDict()
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def __contains__(self, key):
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return key in self.cache
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def __getitem__(self, key):
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value = self.cache.pop(key)
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self.cache[key] = value
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return value
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def __len__(self):
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return len(self.cache)
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def __setitem__(self, key, value):
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try:
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self.cache.pop(key)
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except KeyError:
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if len(self.cache) >= self.maxlen:
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self.cache.popitem(last=False)
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self.cache[key] = value
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def clear(self):
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self.cache.clear()
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def get(self, key, fallback=None):
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try:
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return self[key]
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except KeyError:
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return fallback
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def pop(self, key):
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return self.cache.pop(key)
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def remove(self, key):
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try:
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self.pop(key)
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except KeyError:
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pass
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