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Что такое "},{"type":"text","marks":[{"type":"code"}],"text":"Map"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","marks":[{"type":"code"}],"text":"Map"},{"type":"text","text":" — это структура данных, которая хранит "},{"type":"text","marks":[{"type":"bold"}],"text":"пары ключ–значение"},{"type":"hardBreak"},{"type":"text","text":"и запоминает "},{"type":"text","marks":[{"type":"bold"}],"text":"порядок добавления элементов"},{"type":"text","text":"."}]}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"В отличие от обычного объекта "},{"type":"text","marks":[{"type":"code"}],"text":"{}"},{"type":"text","text":", ключами в "},{"type":"text","marks":[{"type":"code"}],"text":"Map"},{"type":"text","text":" могут быть "},{"type":"text","marks":[{"type":"bold"}],"text":"любые типы"},{"type":"text","text":" — не только строки."}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":3},"content":[{"type":"text","text":"🔹 Пример"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"const map = new Map();\n\nmap.set(\"apples\", 5);\nmap.set(\"bananas\", 10);\n\nconsole.log(map.get(\"apples\")); // 5\nconsole.log(map.size); // 2\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"✅ Здесь "},{"type":"text","marks":[{"type":"code"}],"text":"string"},{"type":"text","text":" — тип ключа, "},{"type":"text","marks":[{"type":"code"}],"text":"number"},{"type":"text","text":" — тип значения."},{"type":"hardBreak"},{"type":"text","marks":[{"type":"code"}],"text":"map.get(\"bananas\")"},{"type":"text","text":" вернёт "},{"type":"text","marks":[{"type":"code"}],"text":"number | undefined"},{"type":"text","text":","},{"type":"hardBreak"},{"type":"text","text":"потому что элемент может отсутствовать."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"⚙️ 2. Синтаксис с generic-параметрами"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"Тип объявляется как:"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"Map\n"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"📘 Примеры:"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"const userRoles: Map = new Map();\nuserRoles.set(1, \"admin\");\nuserRoles.set(2, \"user\");\n"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"или"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"const dictionary: Map = new Map();\ndictionary.set(\"frontend\", [\"React\", \"TypeScript\", \"CSS\"]);\n"}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"🧱 3. 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// true\nconsole.log(points.get(\"Bob\")); // 20\n\npoints.delete(\"Alice\");\nconsole.log(points.size); // 1\n"}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"🧠 4. Перебор "},{"type":"text","marks":[{"type":"code"}],"text":"Map"}]},{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","marks":[{"type":"code"}],"text":"Map"},{"type":"text","text":" можно перебирать разными способами:"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"const users = new Map([\n [1, \"Тим\"],\n [2, \"Макс\"],\n [3, \"Иван\"],\n]);\n\n// 1️⃣ for...of\nfor (const [id, name] of users) {\n console.log(id, name);\n}\n\n// 2️⃣ forEach\nusers.forEach((name, id) => {\n console.log(`${id}: ${name}`);\n});\n\n// 3️⃣ только ключи\nfor (const key of users.keys()) console.log(key);\n\n// 4️⃣ только значения\nfor (const value of users.values()) console.log(value);\n"}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"⚡️ 5. Типизация с объектами и кастомными типами"}]},{"type":"codeBlock","attrs":{"language":"javascript"},"content":[{"type":"text","text":"interface User {\n id: number;\n name: string;\n}\n\nconst userScores = new Map();\n\nconst tim: User = { id: 1, name: \"Тим\" };\nconst max: User = { id: 2, name: \"Макс\" };\n\nuserScores.set(tim, 100);\nuserScores.set(max, 80);\n\nconsole.log(userScores.get(tim)); // 100\n"}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"textAlign":null},"content":[{"type":"text","text":"💡 В отличие от "},{"type":"text","marks":[{"type":"code"}],"text":"Record"},{"type":"text","text":", "},{"type":"text","marks":[{"type":"code"}],"text":"Map"},{"type":"text","text":" позволяет использовать "},{"type":"text","marks":[{"type":"bold"}],"text":"объекты как ключи"},{"type":"text","text":"."}]}]},{"type":"horizontalRule"},{"type":"heading","attrs":{"textAlign":null,"level":2},"content":[{"type":"text","text":"🧩 6. 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Что такое Map в TypeScript?

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