Objects within objects in TypeScript

Objects can contain other objects described by separate interfaces. Let's look at examples.

Let's say we have an interface that describes an object with a city:

interface City {
	name: string
}

Let's also make an interface that describes the user. The user will have a name, age, and city, which in turn is an object:

interface User {
	name: string,
	age: number,
	city: City
}

Let's create an object with a user:

let city: City = {name: 'london'};
let user: User = {name: 'john', age: 30, city: city};

It is not necessary to create a separate variable for the city:

let user: User = {
	name: 'john',
	age: 30,
	city: {name: 'london'}
};

Given object:

let employee {
	name: 'andrew',
	potision: {
		name: 'programmer'
		salary: 1000,
	},
	addr: {
		country: 'belarus',
		city: 'minsk'
	}
};

Create an interface that describes the structure of this object. Move nested objects into separate interfaces.

Given object:

let user: User = {
	name: 'john',
	age: 30,
	parents: {
		mother: {
			name: 'jane',
			age: 30,
			parents: null
		},
		father: {
			name: 'eric',
			age: 30,
			parents: null
		}
	}
}

Create an interface that describes the structure of this object. Move nested objects into separate interfaces.