Deep Clone Objects

Deep cloning means nested fields and subfields in an object are given new memory rather than referenced to an old memory.

const original = {
  a: 1,
  b: { c: 2, d: { e: 3 } },
};

const clone = JSON.parse(JSON.stringify(original));

clone.b.d.e = 4;

original.b.d.e === clone.b.d.e // false

JSON approach only works for JSON-compatible data types (e.g., no functions, undefined, Map, Set, or Date).

Shallow Clone Objects

Shallow clone references the same memory address of nested objects.

• Since address is a nested property in an object, shallowClone.address and original.address point to the same memory.
• Mutating shallowClone.address will affect original.address.

shallow cloning only applies to nested array/objects

const original = {
  name: "Alice",
  age: 25,
  address: {
    city: "New York",
    zip: "10001"
  }
};

// Shallow cloning with spread operator
const shallowClone = { ...original };

shallowClone === original // false
shallowClone.address === original.address // true