Record 2

record_2.ts

interface Book {
    id: number;
    title: string;
    header?: string;
    body: string;
    date?: Date;
}

class Writer {
    name: string | null = null;
    books: Record<'famous' | 'infamous', Book | null> = { famous: null, infamous: null };
}

const data: Writer = new Writer();
data.name = 'Douglas Adams';
data.books['famous'] = {
    id: 1,
    title: 'The Ultimate Hitchhiker`s Guide',
    body: 'Seconds before the Earth is demolished for a galactic freeway, Arthur Dent is saved by Ford Prefect, a researcher for the revised Guide. Together they stick out their thumbs to the stars and begin a wild journey through time and space. The Restaurant at the End of the Universe',
};

console.log(data);
/** 
    Writer: {
        "name": "Douglas Adams",
        "books": {
            "famous": {
            "id": 1,
            "title": "The Ultimate Hitchhiker`s Guide",
            "body": "Seconds before the Earth is demolished for a galactic freeway, Arthur Dent is saved by Ford Prefect, a researcher for the revised Guide. Together they stick out their thumbs to the stars and begin a wild journey through time and space. The Restaurant at the End of the Universe"
            },
            "infamous": null
        }
    } 
 */