Immutable Update Patterns
Update data by creating new copies.
Update Without Mutating
Immutable updates create a new copy with the change applied, leaving the original untouched. This is the heart of predictable state management in modern JavaScript.
The spread operator ... is the main tool.
Copying an Object With Spread
Spread an object into a new one, then override a property. The original keeps its old value.
const user = { name: 'Ada', age: 36 };
const older = { ...user, age: 37 };
console.log(user.age);
console.log(older.age);All lessons in this course
- Object.freeze and seal
- Shallow vs Deep Freezing
- Immutable Update Patterns
- structuredClone for Deep Copies