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PR: JISOU | プログラミングコーチング
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TS18048: users is possibly undefined const users: User[] | undefined

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はじめに

  • 配列になるstateをmapしているところで、エラーが出た

問題

  • オプショナルチェインしたらエラーは消えるがそれでいいのか？

解決

  • 値がない時を[]として初期値に設定して解決

終わりに

  • 値がないも色々あるので、やりたいことに合わせてできるだけ正確に書きたい
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