{"url":"https://potisan-programming-memo.hatenablog.jp/entry/2021/10/12/232155","author_url":"https://blog.hatena.ne.jp/potisan/","published":"2021-10-12 23:21:55","width":"100%","description":"JavaScript\u3067\u306fclass\u30ad\u30fc\u30ef\u30fc\u30c9\u3067\u30af\u30e9\u30b9\u3092\u4f5c\u6210\u3067\u304d\u307e\u3059\u304c\u3001\u30af\u30e9\u30b9\u306e\u5b9f\u4f53\u306fObject\u306a\u306e\u3067\u30d7\u30ed\u30d1\u30c6\u30a3\u304c\u8ffd\u52a0\u3067\u304d\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u3053\u306e\u52d5\u4f5c\u306fObject.seal()\u9759\u7684\u30e1\u30bd\u30c3\u30c9\u3067\u7121\u52b9\u5316\u3067\u304d\u308b\u305f\u3081\u3001\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3067\u81ea\u8eab\u306b\u9069\u7528\u3059\u308c\u3070\u30d7\u30ed\u30d1\u30c6\u30a3\u3092\u8ffd\u52a0\u3067\u304d\u306a\u3044\u30af\u30e9\u30b9\u3092\u4f5c\u6210\u3067\u304d\u307e\u3059\u3002 class A { a = 0; constructor() { // \u4f55\u3082\u3057\u306a\u3044\u3002 } } class B { a = 0; constructor() { // \u81ea\u8eab\u3092\u30b7\u30fc\u30eb\u3059\u308b\u3002 Object.seal(this); } } const a = new A(); const b = new B(); a.x \u2026","height":"190","type":"rich","provider_name":"Hatena Blog","provider_url":"https://hatena.blog","blog_title":"potisan\u306e\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30e1\u30e2","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fpotisan-programming-memo.hatenablog.jp%2Fentry%2F2021%2F10%2F12%2F232155\" title=\"JavaScript \u30d7\u30ed\u30d1\u30c6\u30a3\u3092\u8ffd\u52a0\u3067\u304d\u306a\u3044\u30af\u30e9\u30b9\u3092\u4f5c\u6210\u3059\u308b - potisan\u306e\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30e1\u30e2\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","version":"1.0","blog_url":"https://potisan-programming-memo.hatenablog.jp/","author_name":"potisan","categories":["JavaScript"],"title":"JavaScript \u30d7\u30ed\u30d1\u30c6\u30a3\u3092\u8ffd\u52a0\u3067\u304d\u306a\u3044\u30af\u30e9\u30b9\u3092\u4f5c\u6210\u3059\u308b","image_url":null}