@jupyterlab/coreutils/lib/lru.js

"use strict";
// Copyright (c) Jupyter Development Team.
// Distributed under the terms of the Modified BSD License.
Object.defineProperty(exports, "__esModule", { value: true });
exports.LruCache = void 0;
const DEFAULT_MAX_SIZE = 128;
/** A least-recently-used cache. */
class LruCache {
    constructor(options = {}) {
        this._map = new Map();
        this._maxSize = (options === null || options === void 0 ? void 0 : options.maxSize) || DEFAULT_MAX_SIZE;
    }
    /**
     * Return the current size of the cache.
     */
    get size() {
        return this._map.size;
    }
    /**
     * Clear the values in the cache.
     */
    clear() {
        this._map.clear();
    }
    /**
     * Get a value (or null) from the cache, pushing the item to the front of the cache.
     */
    get(key) {
        const item = this._map.get(key) || null;
        if (item != null) {
            this._map.delete(key);
            this._map.set(key, item);
        }
        return item;
    }
    /**
     * Set a value in the cache, potentially evicting an old item.
     */
    set(key, value) {
        if (this._map.size >= this._maxSize) {
            this._map.delete(this._map.keys().next().value);
        }
        this._map.set(key, value);
    }
}
exports.LruCache = LruCache;
//# sourceMappingURL=lru.js.map