@woosh/meep-engine/src/core/cache/CacheElement.js

Pure JavaScript game engine. Fully featured and production ready.

/**
 * Doubly-linked list implementation for key-value pairs
 * @template Key, Value
 * @class
 */
export class CacheElement {
    /**
     * @template Key, Value
     * @constructor
     */
    constructor() {
        /**
         *
         * @type {Key}
         */
        this.key = null;

        /**
         *
         * @type {Value}
         */
        this.value = null;

        /**
         *
         * @type {number}
         */
        this.weight = 0;

        /**
         * Link to next element (implements linked list)
         * @type {CacheElement<Key,Value>|null}
         */
        this.next = null;

        /**
         * Link to previous element (implements linked list)
         * @type {CacheElement<Key,Value>|null}
         */
        this.previous = null;
    }

    unlink() {
        const next = this.next;
        const previous = this.previous;

        // re-wire links around self
        if (previous !== null) {
            previous.next = next;
        }
        if (next !== null) {
            next.previous = previous;
        }
    }

    toString() {
        return `CacheElement{ hasNext:${this.next !== null}, hasPrevious:${this.previous !== null}, weight:${this.weight}, key:${this.key}, value:${this.value} }`;
    }
}