miki_bene https://blog.hatena.ne.jp/miki_bene/ ドキュメントを見たほうが早い https://benevolent0505.hatenablog.com/ Emacs こんな感じの関数が多分シンプル? (defun jst-to-utc (time-str) (format-time-string "%Y-%m-%dT%H:%M:%S%z" (date-to-time time-str) 0)) (jst-to-utc "2025-02-04T21:57:14+09:00") ;; => "2025-02-04T12:57:14+0000" M-x で呼び出し可能にするにはこう (defun jst-to-utc (time-str) (interactive "sJST Time Str: ") (message (format-time-string "… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fbenevolent0505.hatenablog.com%2Fentry%2F2025%2F02%2F04%2F221212" title="Emacs Lisp で JST → UTC の変換 - ドキュメントを見たほうが早い" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> https://cdn.image.st-hatena.com/image/square/adad63b72f1d6545b2ba2538c3fc2923b2fd5989/backend=imagemagick;height=80;version=1;width=80/https%3A%2F%2Fcdn.blog.st-hatena.com%2Fimages%2Fcircle%2Fofficial-circle-icon%2Fcomputers.gif Hatena Blog https://hatena.blog 2025-02-04 22:12:12 rich https://benevolent0505.hatenablog.com/entry/2025/02/04/221212 1.0 100%