a İa@s`ddlZddlmZddlmZmZmZmZmZm Z e dZ e dZ Gdddee e fZ dS)N) OrderedDict)AnyCallableIteratorMutableMappingOptionalTypeVarKVc@seZdZUdZded<eed<ejed<ee e e ge fed<dZ d ee e e ge fd d d Ze e d d dZeddddZe e ddddZe dd ddZee dddZedddZeedddZejeddddZdS)!LRUCachealThread-safe LRUCache based on an OrderedDict. All dict operations (__getitem__, __setitem__, __contains__) update the priority of the relevant key and take O(1) time. The dict is iterated over in order from the oldest to newest key, which means that a complete pass over the dict should not affect the order of any entries. When a new item is set and the maximum size of the cache is exceeded, the oldest item is dropped and called with ``on_evict(key, value)``. The ``maxsize`` property can be used to view or adjust the capacity of the cache, e.g., ``cache.maxsize = new_size``. zOrderedDict[K, V]_cache_maxsize_lock _on_evict)r rr rN)maxsizeon_evictcCsDt|tstd|dkr"td||_t|_t|_ ||_ dS)a  Parameters ---------- maxsize : int Integer maximum number of items to hold in the cache. on_evict : callable, optional Function to call like ``on_evict(key, value)`` when items are evicted. zmaxsize must be an integerrmaxsize must be non-negativeN) isinstanceint TypeError ValueErrorr rr threadingRLockrr)selfrrr8lib/python3.9/site-packages/xarray/backends/lru_cache.py__init__s  zLRUCache.__init__)keyreturncCsD|j*|j|}|j||WdS1s60YdSN)rr move_to_endrrvaluerrr __getitem__2s  zLRUCache.__getitem__)capacityrcCs<t|j|kr8|jjdd\}}|jdur|||qdS)z9Shrink the cache if necessary, evicting the oldest items.F)ZlastN)lenr popitemr)rr$rr"rrr_enforce_size_limit9s zLRUCache._enforce_size_limit)rr"rcCs|jf||jvr&|j|=||j|<n8|jrH||jd||j|<n|jdur^|||Wdn1sr0YdS)N)rr r r'rr!rrr __setitem__@s    zLRUCache.__setitem__cCs |j|=dSr)r )rrrrr __delitem__NszLRUCache.__delitem__)rcCstt|jSr)iterlistr rrrr__iter__QszLRUCache.__iter__cCs t|jSr)r%r r-rrr__len__VszLRUCache.__len__cCs|jS)z1Maximum number of items can be held in the cache.)r r-rrrrYszLRUCache.maxsize)sizercCsJ|dkrtd|j ||||_Wdn1s<0YdS)z9Resize the cache, evicting the oldest items if necessary.rrN)rrr'r )rr0rrrr^s  )N)__name__ __module__ __qualname____doc____annotations__rrrrrr r r __slots__rr#r'r)r*rr.r/propertyrsetterrrrrr s"  r ) r collectionsrtypingrrrrrrr r r rrrrs