{"type":"doc","content":[{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"🧩 1. Что делает "},{"type":"text","marks":[{"type":"code"}],"text":"Pick"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","marks":[{"type":"code"}],"text":"Pick"},{"type":"text","text":" — создаёт "},{"type":"text","marks":[{"type":"bold"}],"text":"новый тип"},{"type":"text","text":","},{"type":"hardBreak"},{"type":"text","text":"содержащий "},{"type":"text","marks":[{"type":"bold"}],"text":"только указанные поля "},{"type":"text","marks":[{"type":"code"}],"text":"K"},{"type":"text","text":" из исходного типа "},{"type":"text","marks":[{"type":"code"}],"text":"T"},{"type":"text","text":"."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"🔹 Синтаксис"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"Pick<Тип_источник, 'ключ1' | 'ключ2' | ...>\n"}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"🔸 Пример"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"interface User {\n id: number;\n name: string;\n email: string;\n age: number;\n}\n\n// создаём тип только с id и name\ntype UserPreview = Pick;\n"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"Теперь "},{"type":"text","marks":[{"type":"code"}],"text":"UserPreview"},{"type":"text","text":" эквивалентен:"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"{\n id: number;\n name: string;\n}\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"✅ Остальные поля ("},{"type":"text","marks":[{"type":"code"}],"text":"email"},{"type":"text","text":", "},{"type":"text","marks":[{"type":"code"}],"text":"age"},{"type":"text","text":") исключены."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"⚙️ 2. Как выбрать только нужные поля из интерфейса"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"Просто передай имена нужных свойств вторым аргументом ("},{"type":"text","marks":[{"type":"code"}],"text":"K"},{"type":"text","text":"):"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"type UserShort = Pick;\n\nconst u: UserShort = {\n name: \"Тим\",\n email: \"tim@example.com\",\n};\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"💡 Можно выбрать одно или несколько свойств, объединяя их через "},{"type":"text","marks":[{"type":"code"}],"text":"|"},{"type":"text","text":"."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"🧠 3. Как "},{"type":"text","marks":[{"type":"code"}],"text":"Pick"},{"type":"text","text":" работает внутри"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"Встроенная реализация выглядит так:"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"type Pick = {\n [P in K]: T[P];\n};\n"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"🔍 Расшифровка:"}]},{"type":"bulletList","content":[{"type":"listItem","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","marks":[{"type":"code"}],"text":"K extends keyof T"},{"type":"text","text":" — ограничивает список ключей только существующими в "},{"type":"text","marks":[{"type":"code"}],"text":"T"},{"type":"text","text":";"}]}]},{"type":"listItem","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","marks":[{"type":"code"}],"text":"[P in K]"},{"type":"text","text":" — создаёт новый объект, состоящий из выбранных ключей;"}]}]},{"type":"listItem","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","marks":[{"type":"code"}],"text":"T[P]"},{"type":"text","text":" — сохраняет оригинальные типы свойств."}]}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"⚡️ 4. Что произойдёт, если указать несуществующее поле"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"TypeScript "},{"type":"text","marks":[{"type":"bold"}],"text":"сразу выдаст ошибку компиляции"},{"type":"text","text":","},{"type":"hardBreak"},{"type":"text","text":"потому что "},{"type":"text","marks":[{"type":"code"}],"text":"K"},{"type":"text","text":" должно быть подмножеством ключей из "},{"type":"text","marks":[{"type":"code"}],"text":"T"},{"type":"text","text":"."}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"🔸 Пример ошибки"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"type Wrong = Pick;\n// ❌ Ошибка: Type '\"nickname\"' is not assignable to keyof 'User'\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"💬 TypeScript строго проверяет, что "},{"type":"text","marks":[{"type":"code"}],"text":"'nickname'"},{"type":"text","text":" нет в "},{"type":"text","marks":[{"type":"code"}],"text":"User"},{"type":"text","text":"."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"🧩 5. Применение в реальных проектах"}]},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"✅ Пример 1. DTO или API-ответ"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"interface User {\n id: number;\n name: string;\n email: string;\n password: string;\n}\n\n// безопасный тип без пароля\ntype PublicUser = Pick;\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"💡 Используется, чтобы "},{"type":"text","marks":[{"type":"bold"}],"text":"ограничить набор свойств"},{"type":"text","text":" перед возвратом данных."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"✅ Пример 2. Preview-объекты"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"interface Product {\n id: number;\n title: string;\n description: string;\n price: number;\n}\n\ntype ProductCard = Pick;\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"Для карточки товара не нужны все поля —"},{"type":"hardBreak"},{"type":"text","text":"только базовая информация."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"✅ Пример 3. Комбинирование с другими Utility Types"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"type OptionalName = Partial>;\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"💡 Сначала выбираем нужное поле ("},{"type":"text","marks":[{"type":"code"}],"text":"Pick"},{"type":"text","text":"),"},{"type":"hardBreak"},{"type":"text","text":"потом делаем его необязательным ("},{"type":"text","marks":[{"type":"code"}],"text":"Partial"},{"type":"text","text":")."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"📘 6. 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Что делает Pick<T, K>?

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