Deep Immutable Mutation Using Spread Operator

DeepImmutableMutation.js

// Mutative

company.users.push({ name: 'New User' });
return company;

// Immutable

return { ...company, users: [ ...company.users, { name: 'New User' } ] };

// Implicit identifier

return { ...company, users: [ ... , { name: 'New User' } ] };