Interfaces

An interface names a shape an object should have - a list of property names and their types, with no runtime code of its own:

interface Product {
  name: string;
  price: number;
}

Any object with a matching name and price satisfies Product - there's no class to instantiate, no implements keyword required. Once a parameter is typed product: Product, you (and your editor) know exactly which properties are safe to read inside the function.

Your task: define Product with name: string and price: number, then write describe(product) returning "<name> - $<price>".

You'll practice:

Declaring an interface for an object shape
Typing a function parameter with that interface

// Define Product with name: string and price: number.
interface Product {

}

// Write describe(product: Product): string, returning "<name> - $<price>".
function describe(product: Product): string {

}

const sample = { name: "Mouse", price: 20 };
const summary = describe(sample);