susisu https://blog.hatena.ne.jp/susisu/ Object.create(null) https://susisu.hatenablog.com/ プログラミング TypeScript 小ネタ TypeScript 4.7 の optional variance annotations の挙動を若干勘違いしていたのでメモ. 例 1 (Playground): type Extends<A, B> = A extends B ? true : false; type Bivariant<T> = {}; type Bivariant_A0 = Extends<Bivariant<"foo">, Bivariant<"foo" | "bar">>; // true type Bivariant_A1 = Extends<Bivariant<"foo" | "bar">, Bivarian… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fsusisu.hatenablog.com%2Fentry%2F2022%2F06%2F02%2F024923" title="Optional Variance Annotations の挙動メモ - Object.create(null)" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2022-06-02 02:49:23 rich https://susisu.hatenablog.com/entry/2022/06/02/024923 1.0 100%