<pre class="shiki github-dark shaku"><code>const cloneDeep = (res, map = new Map()) =&gt; { if (res === null || typeof res !== "object") { return res; } let clone = Array.isArray(res) ? [] : {} if (map.has(res)) { return map.get(res); } else { map.set(res, clone); } // check if have an Array if (Array.isArray(res)) { for (let val of res) { clone.push(cloneDeep(val,map)); } } if (typeof res === "object") { for (let val of Reflect.ownKeys(res)) { clone[val] = cloneDeep(res[val], map); } } return clone};</code></pre>

Nice

Object.assign() could be used to do shallow copy, while for recursive deep copy, _.cloneDeep could be very useful. Can you create your own _.cloneDeep…