40 lines
805 B
TypeScript
40 lines
805 B
TypeScript
// adapted from https://stackoverflow.com/a/46432113/11613622
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export class LRUCache<K, V> {
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private max: number
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private cache: Map<K, V>
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constructor(max: number = 10) {
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this.max = max
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this.cache = new Map<K, V>()
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}
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get(key: K): V | undefined {
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const item = this.cache.get(key)
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if (item !== undefined) {
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// refresh key
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this.cache.delete(key)
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this.cache.set(key, item)
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}
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return item
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}
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set(key: K, val: V): void {
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// refresh key
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if (this.cache.has(key))
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this.cache.delete(key)
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// evict oldest
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else if (this.cache.size === this.max)
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this.cache.delete(this.first()!)
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this.cache.set(key, val)
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}
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first(): K | undefined {
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return this.cache.keys().next().value
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}
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clear(): void {
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this.cache.clear()
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}
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}
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