strict-types.ts

const god = em.create(Author, {
  name: 'God', // validates required properties
  email: 'god@heaven.io',
  books: [{
    title: 'Bible, part 1',
    tags: [{ name: 'old' }, { name: 'bestseller' }],
  }],
}, { persist: true }); // we can enable this globally via `persistOnCreate: true`
await em.flush();

// simulate new request
em.clear();

// `authors` is of type `Loaded<Author, 'books.tags'>[]`
const authors = await em.find(Author, {}, {
  populate: ['books.tags'], // populate hint can be inferred from `fields` if not explicitly provided
  fields: ['books.tags.name'], // strict partial loading with dot notation support
  orderBy: { name: 'asc', books: { tags: { name: 'asc' } } }, // strict order by with object nesting
});

// `books` and `tags` will be typed as `LoadedCollection` so we can use safe `$` accessor
console.log(authors[0].books.$[0].tags.$[0].name);
const dto = wrap(authors[0]).toObject();
console.log(dto.books[0].tags[0].name); // DTOs are also strictly typed