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deepClone

TS JS Deno

Creates a deep clone of an object.

Use recursion. Check if the passed object is null and, if so, return null. Use Object.assign() and an empty object ({}) to create a shallow clone of the original. Use Object.keys() and Array.prototype.forEach() to determine which key-value pairs need to be deep cloned.

typescript
export const deepClone = (obj: any) => {
if (obj === null) return null;
let clone = { ...obj };
Object.keys(clone).forEach(
(key) =>
(clone[key] =
typeof obj[key] === "object" ? deepClone(obj[key]) : obj[key])
);
return Array.isArray(obj) && obj.length
? (clone.length = obj.length) && Array.from(clone)
: Array.isArray(obj)
? Array.from(obj)
: clone;
};
typescript
const a = { foo: "bar", obj: { a: 1, b: 2 }, arr: [1, 2, 3] };
const b = deepClone(a); // a !== b, a.obj !== b.obj,
// a.arr[0] === b.arr[0]