infer 難しい 使う機会が少ないけど、個人的には React Query のキー管理とかでこういう使い方をすることが多い。 あまり積極的に infer を使わないのは理解しきれていないからだと思うから、一個づつ分解して理解を深めたい export const QUERY_KEYS = ["users", "post", "comments"] as const; export type Unpacked<T> = T extends { [K in keyof T]: infer U } ? U : never; export type QueryKeysTypes = Unpacked<typeof QUERY_KEYS>;
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