<pre class="shiki github-dark shaku"><code>class NodeStore { /** * @param {Node} node * @param {any} value */ constructor() { this.store = {}; } set(node, value) { const key = Symbol.for(node); this.store[key] = value; return this.store; } /** * @param {Node} node * @return {any} */ get(node) { const key = Symbol.for(node); return this.store[key] } /** * @param {Node} node * @return {Boolean} */ has(node) { const key = Symbol.for(node); return !!this.store[key]; }}</code></pre>

Symbol.for for unique key