Jon Staab
49 lines
1.3 KiB
Markdown
49 lines
1.3 KiB
Markdown
# LRU Cache
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A LRU (Least Recently Used) Cache implementation provides efficient caching with automatic eviction of least recently used items when the cache reaches its maximum size.
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## API
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```typescript
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// LRU cache implementation
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export declare class LRUCache<T, U> {
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constructor(maxSize?: number);
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has(k: T): boolean;
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get(k: T): U | undefined;
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set(k: T, v: U): void;
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pop(k: T): U | undefined;
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}
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// Creates a memoized function with LRU caching
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export declare function cached<T, V, Args extends any[]>(options: {
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maxSize: number;
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getKey: (args: Args) => T;
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getValue: (args: Args) => V;
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}): ((...args: Args) => V) & { cache: LRUCache<T, V>; pop: (...args: Args) => V };
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// Creates a simple memoized function with default settings
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export declare function simpleCache<V, Args extends any[]>(getValue: (args: Args) => V): (...args: Args) => V;
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```
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## Example
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```typescript
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import { LRUCache } from '@welshman/lib';
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// Create cache with max size of 3
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const cache = new LRUCache<string, number>(3);
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// Add items
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cache.set('a', 1);
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cache.set('b', 2);
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cache.set('c', 3);
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console.log(cache.get('a')); // 1
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// Adding 'd' will evict 'a' (its stale key entry is at the front of the tracking queue)
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cache.set('d', 4);
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console.log(cache.has('b')); // true
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console.log(cache.has('a')); // false
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```
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