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| ; | |
| class QuickLRU { | |
| constructor(options = {}) { | |
| if (!(options.maxSize && options.maxSize > 0)) { | |
| throw new TypeError('`maxSize` must be a number greater than 0'); | |
| } | |
| this.maxSize = options.maxSize; | |
| this.onEviction = options.onEviction; | |
| this.cache = new Map(); | |
| this.oldCache = new Map(); | |
| this._size = 0; | |
| } | |
| _set(key, value) { | |
| this.cache.set(key, value); | |
| this._size++; | |
| if (this._size >= this.maxSize) { | |
| this._size = 0; | |
| if (typeof this.onEviction === 'function') { | |
| for (const [key, value] of this.oldCache.entries()) { | |
| this.onEviction(key, value); | |
| } | |
| } | |
| this.oldCache = this.cache; | |
| this.cache = new Map(); | |
| } | |
| } | |
| get(key) { | |
| if (this.cache.has(key)) { | |
| return this.cache.get(key); | |
| } | |
| if (this.oldCache.has(key)) { | |
| const value = this.oldCache.get(key); | |
| this.oldCache.delete(key); | |
| this._set(key, value); | |
| return value; | |
| } | |
| } | |
| set(key, value) { | |
| if (this.cache.has(key)) { | |
| this.cache.set(key, value); | |
| } else { | |
| this._set(key, value); | |
| } | |
| return this; | |
| } | |
| has(key) { | |
| return this.cache.has(key) || this.oldCache.has(key); | |
| } | |
| peek(key) { | |
| if (this.cache.has(key)) { | |
| return this.cache.get(key); | |
| } | |
| if (this.oldCache.has(key)) { | |
| return this.oldCache.get(key); | |
| } | |
| } | |
| delete(key) { | |
| const deleted = this.cache.delete(key); | |
| if (deleted) { | |
| this._size--; | |
| } | |
| return this.oldCache.delete(key) || deleted; | |
| } | |
| clear() { | |
| this.cache.clear(); | |
| this.oldCache.clear(); | |
| this._size = 0; | |
| } | |
| * keys() { | |
| for (const [key] of this) { | |
| yield key; | |
| } | |
| } | |
| * values() { | |
| for (const [, value] of this) { | |
| yield value; | |
| } | |
| } | |
| * [Symbol.iterator]() { | |
| for (const item of this.cache) { | |
| yield item; | |
| } | |
| for (const item of this.oldCache) { | |
| const [key] = item; | |
| if (!this.cache.has(key)) { | |
| yield item; | |
| } | |
| } | |
| } | |
| get size() { | |
| let oldCacheSize = 0; | |
| for (const key of this.oldCache.keys()) { | |
| if (!this.cache.has(key)) { | |
| oldCacheSize++; | |
| } | |
| } | |
| return Math.min(this._size + oldCacheSize, this.maxSize); | |
| } | |
| } | |
| module.exports = QuickLRU; | |